UPDATE June 14, 2018:

Virginia State Police confirmed the identity of remains found along the median near mile marker 141 on Interstate 95 in Stafford back in 1991 as Marta Haydee Rodriguez, Jose Rodriguez's wife who went missing from Arlington County in 1989, WDCW reports. Not far from that location, Pamela Butler is also believed to be buried.

UPDATE April 8, 2017: Pamela Butler's former boyfriend Jose Rodriguez Cruz was arrested for first-degree murder in Arlington, Va., Metro D.C. Police announced Saturday.

Jose Rodriguez Cruz waived extradition and was in custody of Metropolitan D.C. Police.

Metro D.C. Police held a news conference at 11:30 a.m. ET Saturday to give details about the case.

Butler was declared dead in January. Police said Butler's body has not been found.

Police said they believe this is a domestic-violence case.

UPDATE Jan. 19, 2017: Pamela Butler has been declared dead. Her manner of death has been declared as "unknown."

Pamela Butler was a highly successful computer specialist for the Environmental Protection Agency in Washington, D.C., raking in a cushy six-figure salary.

Her brother Derrick Butler says she was a lovable loner who kept an immaculate house on the city's northwest side.

"Pam's house was almost too neat -- if you were in there you'd be scared to sit down," said Derrick. "I mean she was just that neat."

It was a normally safe area, but a string of recent arsons had Pamela on edge. As a precaution, Pamela installed a sophisticated security system with alarms, motion-activated lights and surveillance cameras covering almost every inch of the house. The left side of the house was the only side not covered by surveillance camera.

Pamela had always erred on the side caution. That's why Derrick was a little surprised when his sister went looking for love online and met Jose Rodriguez-Cruz, a former military police officer.

"He acted like a gentleman to me, so I thought he was a nice guy," said Thelma Butler, Pamela's 84-year-old mother.

Both Pamela and Jose are in their 40s, long-time divorced, and yearning for new love.

By Valentine's Day, friends say Pamela and Jose are in the midst of a whirlwind romance. But instead of a romantic dinner for two, the happy couple of five months make plans a few days earlier to take Thelma out.

"I said 'Pam, do you realize that it's Valentine's Day, you don't wanna be bothered by me, probably want to be out by yourself,'" said Thelma. "She said 'No mom, we'll pick you up at 3 o'clock,' and I said 'OK, fine.'"

But when Valentine's Day arrives, poor Thelma waits and waits and waits.

"Three o'clock on Saturday comes, I was like 'Maybe they're a little late,'" said Thelma. "Four o'clock, 5, I start calling, 6 -- all the way to 10 o'clock."

"She started calling Pam, Pam didn't answer the telephone, and she really got concerned," said Derrick.

Derrick figures his sister and Jose simply had a change of heart and went on a last-minute Valentine's getaway.

"I kind of brushed it off, thinking it's a new boyfriend, they're just out having a good time somewhere," said Derrick.

Two more days pass -- still no calls or texts from Pamela. Thelma's motherly instincts tell her daughter is in trouble

"I said 'We got to go up there, something is definitely wrong,'" said Thelma.

When they get to Pamela's house, both of her luxury cars are sitting in her driveway. Her front door is locked. But her burglar alarm isn't turned on.

"That was a red flag for me," said Derrick.

Inside they find Pamela's purse and wallet, but the keys to both cars are missing.

"Didn't see any signs of blood, any signs of a struggle, nothing knocked over," said Derrick.

There are no obvious signs of foul play, yet her family finds something unsettling around every corner.

"The first thing that caught my eyes was a latex glove on the floor by the leg of her table, a blue latex glove," said Thelma.

"She had files that were sitting on the floor," said Derrick. "She would never leave her house looking like that."

"On the desk of the table was a note: 'Pam, where are you? Are we still taking your mother to dinner? I've been here looking for you,'" said Thelma.

"I went upstairs and I looked and the sheets were off her bed, I saw that, I said 'Yeah, something isn't right,'" said Derrick.

Her mattress is bare and her comforter is heaped on a settee, completely out of character for the impeccably tidy Pamela.

"Then we noticed the window. She had these type of blinds you could either lower them from the top or lift them up from the bottom," said Derrick. "My mother looked at the window, said 'the blind's lifted up, Pam don't lift the blinds up, she lowers them down from the top.' Then we went over to the window and the window was unlocked."

It's the only window in the house that's unlocked, and it's also on that side of the house that's not covered by the surveillance camera.

Derrick jumps in his car and heads to Jose's apartment. His gut tells him Jose may know where Pamela is.

"I told him Pam's missing, normally when these things happen you look at the boyfriend -- I said we're looking at you," said Derrick.

And then Jose drops a bombshell:

"He said 'Me and Pam broke up, and he said he hadn't talked to her," said Derrick. "One time he says [they broke up] Thursday. The other time he says they broke up on Friday. He said 'I'm just devastated but I didn't do anything to Pam.'"

Derrick finds that strange: If they broke up the day before Valentine's Day, why would Jose have left that note? And Pamela never called her mom to cancel their plans.

"I know if somebody does something to Pam that she's gonna fight, he's gonna have some scratches or something on him," said Derrick. "I told him, I said 'Jose,' I said 'I need you to take your clothes off.'

"I didn't see any scratches on him but I did see wounds on his back -- cuts, but they were old cuts," said Derrick. "I asked him where'd these come from, he said, 'Oh, an ex-girlfriend tried to kill me.'"

An article in the Washington Post confirmed Jose was in an abusive relationship in the past. But no one was ever charged in the incident.

While Derrick is grilling Jose, his phone suddenly lights up with a wave of incoming calls.

"My mother, my nephew and my sister, they're calling me and telling me 'Derrick, get out of his house, you need to get out of there now, get out of there.' They said 'Derrick, you need to see the surveillance system.'"

"I believe she was put out of that window and put in the car and taken somewhere, love to know where," said Derrick.

D.C. Police also suspect foul play

"There's no explanation for her disappearance, which is another reason that we are acting the way we acted with crime scene coming in, mobile crime coming in and working the case for weeks and weeks on end," said D.C. Metropolitan Police Lt. Christopher Kauffman.

Using the video from Pamela's security system, data obtained from her phone and computer, and eyewitness accounts, they piece together a timeline of events.

"Pam was seen going into the house on Thursday, approximately about 5 o'clock," said Derrick.

At 9:48 p.m. that same night a camera catches Pamela reaching out the door to grab her mail. It's the last image ever captured of Pamela. Police believe Pamela was inside her home on Friday.

"She'd made multiple emails between coworkers, so we think she was alive and well upwards of Friday the 13th," said Kauffman.

Police took Pam's surveillance video from the family, and are not releasing it. But Derrick says Jose is seen going into Pamela's house Friday evening around 8 p.m. Jose claims Pamela abruptly broke up with him. A camera captures him leaving at 11:30 p.m.

Before cops confiscated video, the Butlers scroll through hours of it until they find a clue.

"The whole time that she was missing, nobody ever comes up to her house but Jose, the mailman and the UPS man," said Derrick.

Jose returns Saturday, Valentine's Day, and stays for two hours.

"It showed Jose going in and out of the house with bags," said Thelma.

He returns Sunday for 30 minutes, and again Monday for 90 minutes, removing more bags.

Police want to know what he was doing during that time. They initially focus their investigation on Jose, searching his apartment, seizing his car and questioning him about those bags he was carrying. Cops won't tell us what he said. But Jose told the Washington Post that he was just retrieving his belongings.

"We don't know why she went missing as of right now," said Kauffman.

Derrick claims police asked Jose to take a lie-detector test, but he refuses. Cops tell us this is still an active investigation, and there is little they can say. But to this day, Jose has never been named a suspect, or charged with any crime.

"My theory is Pam found out something about him that she didn't like and I believe she told him she was through, and she walked him to the door and as she was going to that door, he snapped," said Derrick.

Derrick is so convinced Jose hurt her that he returns to Jose's apartment and demands he take the police lie-detector test.

"It was hard but I talked to him for an hour and he said he'd do it, said 'I'll take the polygraph,'" said Derrick.

The morning of the scheduled polygraph, Derrick drives Jose to take the test.

"We're three or four blocks away from Valley Crimes Unit," said Derrick. "I stop at the light and he opens the door, jumps out the car and runs. I was getting ready to get out of the car and go look for him, and he comes back.

"I asked him, 'What's wrong with you?' He said 'Man, I had to go to the bathroom. I couldn't hold it. I had to go to the bathroom,'" said Derrick. "So, looking at him, it's just, something isn't right here."

Derrick says once inside the polygraph room, Jose freaks out.

"He says 'I'm not doing it, take this off of me,' and he went to start trying to pull it off and I said 'No, hold it, don't do that,'" said Derrick. "While they are taking the stuff off of him he is going off, just raving about 'I will kill all you in here. Y'all don't know who you are messing with.' I'm looking at him. I didn't see that side of him at all."

Jose admitted to the Washington Post that he suffers from post-traumatic stress disorder from his years of military service, and that as the lie-detector questioning was about to start his anger at being accused boiled over. He maintains he had nothing to do with Pamela's disappearance.

Crime Watch Daily tracked Jose's last-known address to an apartment complex in Maryland, where we spot a woman we believe to be his girlfriend. The young woman asks us not to show her face, and then says she hasn't dated, seen or even spoken to Jose in years.

A neighbor tells us they see Jose here all the time with the woman we questioned.

For now Jose lives under the aura of suspicion, and the police and the Butlers continue looking for answers.

"She's not been seen or heard of since 2009," said Lt. Kauffman. "That's five Christmases, five mother's days, five birthdays, five Fourth of July's, no one's seen her, so the family deserves answers, the community deserves answers, and we're trying to get answers to those people."

Every year the Butlers, friends and even law enforcement hold a candlelight vigil honoring Pamela. This year's will be very different.

"We're going to declare her dead," said Derrick. "That's going to be very hard. It will give us a little closure."

If you know anything about Pamela Butler's disappearance, you can submit a tip to Crime Watch Daily, or call or text our toll-free tip line at (844) 800-CRIME.