A 41-year-old man who claimed to have a classified military past killed three people inside his neighbor’s house after a domestic dispute with his wife and then fatally shot himself during a standoff with police, authorities say.

Christopher Wilson Snyder, of Brookeville, Maryland, was found dead inside his home Monday night, more than six hours after the fatal shootings next door, the Montgomery County Police Department said.

Snyder’s 33-year-old wife told police that she was held hostage by her husband in their home in the 22000 block of Brown Farm Way over the weekend, Montgomery County Police Chief J. Thomas Manger said at a press briefing after the standoff ended. His wife said she was able to escape Monday and fled to her neighbor’s house. Chris Snyder followed her there and opened fire, killing three people. His wife was able to escape along with two others.

Washington Post pix of Christopher Snyder the man who held wife captive for the weekend before killing 3 at a neighbors house after she escaped. He then killed himself. 1 victim, a contractor found dead outside, is from #OwingsMills. pic.twitter.com/vbQEqYHv3n — Mike Schuh WJZ (@MikeWJZ) May 9, 2018

The victims have been identified as Mary Olson, 66, Danny Lee Murphy, 70; and Craig Harold Shotwell, 54, WJLA-TV reports.

Tonight at 11 – We’re sharing new details about the #Brookeville triple homicide victims and the suspect Chris Snyder. pic.twitter.com/kEE6wa8Nki — Anna-Lysa Gayle (@ABC7Annalysa) May 9, 2018

Little record of Snyder’s life exists online, at least under his real name. Neighbors have said he made references to working for federal clandestine agencies and court documents show that he asked to have his divorce from his previous wife sealed because his secretive military work could put their lives in danger. Snyder appears to have been working as a private contractor in recent years, registering a licensed gun dealership and security company at his home and operating a self-defense and martial arts gym under a fake name.

Manger said they have had “a number of contacts with this suspect in the past over a number of different issues.” Manger did not release any other information about those incidents, and said further details would be revealed at a later time.

Here’s what you need to know about Christopher Snyder and the incident:

1. Snyder Killed His Neighbor, His Neighbor’s Guest & a Person Who Was Working at the Home Before Barricading Himself Inside His Own House for Several Hours, Police Say

Several fatally shot in Brookeville houseMontgomery County police are investigating reports of multiple people found shot in a house in Brookeville. Police were called around 3:45 p.m. Monday to the 22000 block of Brown Farm Police tweeted at 5:48 p.m. that residents in the area should shelter in place. Authorities said multiple fatalities were reported. Police said they could not… 2018-05-07T22:19:14.000Z

Christopher Snyder entered his neighbor’s home in pursuit of his wife, Montgomery County Police Chief J. Thomas Manger told reporters. There were six people inside the home and Snyder fatally shot three of them. The other three, including Snyder’s wife, were able to flee to safety. Manger said a person who lived in the home, a guest and a person who was working there were killed in the shooting.

Police said Mary Olson lived in the home. Her friend, Danny Lee Murphy, of Brandon, South Dakota, was visiting at the time of the shooting. The third victim, Craig Harold Shotwell, of Owings Mills, Maryland, was a contractor doing work at the home, according to police.

NEW: Photo of Mary Olson, killed by a neighbor at her Brookeville home Monday. "Mary was a wonderful person, one of the kindest we know. Always volunteering and helping others," Olson's younger sister told @VictoriaSanchez. Olson is survived by her husband + two adult children. pic.twitter.com/ths8G21oV8 — Kevin Lewis (@ABC7Kevin) May 8, 2018

NEW: Here is a photo of Craig Shotwell, killed in Brookeville. The 54yo was doing work at home. According to bio on company website, Your Home Solutions, LLC, Shotwell is married with two children. He enjoyed riding four wheelers with his kids + collecting wildlife to study. pic.twitter.com/vIBboaRayt — Kevin Lewis (@ABC7Kevin) May 8, 2018

Manger said they received multiple 911 calls about 3:45 p.m. reporting a possible domestic situation involving a person with a gun. “Each caller had various pieces of information and the 911 calltakers attempted to gather as many details as we could. The calltakers heard what sounded like gunshots in the background during some of the 911 calls. Officers responded to 22002 Brown Farm Way and located three deceased adults at the home. All three victims had been shot. Officers secured the home and determined the suspect, Christopher Snyder, had fled.”

After the shooting, Snyder went back to his home, located across the street at 22001 Brown Farm Way, and barricaded himself inside. Residents were told to shelter in place and the neighborhood was locked down. Photos and videos from the scene showed police, including tactical units, flocking to the area along with other emergency responders.

NEW: I just spoke with one of Chris Snyder's friends. Snyder called him yesterday at 3:42 p.m., *two* minutes before the first 911 call led police to the triple murder. That friends now wishes he'd answered. Note: Snyder was known for blocking his number whenever making calls. pic.twitter.com/roKOMSCDuQ — Kevin Lewis (@ABC7Kevin) May 9, 2018

The Montgomery County Police Department tweeted at 10:48 p.m., “We can confirm that the suspect of these homicides is in his home on Brown Farm Way. Our negotiators have been speaking with him via phone. He is refusing to come out of the home.”

According to Manger, the negotiations, “went on for several hours.” About 11 p.m., a police tactical team breached the front door, Manger said. Snyder was on the phone with negotiators at the time. He asked the negotiator, “Did they just break down the front door?” and then hung up the phone, according to the police chief. Officers who were outside the home heard a single gunshot at that time. Snyder was found dead in his home from an apparent self-inflicted gunshot wound, Manger said.

2. Police Say They Knew There Were Numerous Guns Inside the Home & They Were Also Concerend About Possible Explosives

Suspect found dead hours after triple-shooting in BrookevilleThree people were fatally shot in a house in Brookeville, three others were able to escape and the suspect was found dead hours later, Montgomery County police said. Police were called around 3:44 p.m. Monday to the 22000 block of Brown Farm Way for a possible domestic situation involving a person with a gun. Montgomery… 2018-05-08T04:18:08.000Z

Montgomery County Police Chief J. Thomas Manger told reporters that the department’s tactical team was conducting a “slow, methodical search” of Snyder’s home because during the negotiations there was “some discussion of explosives.”

Manger added, “we also know that there are a number of guns in the home. So we are currently searching the home. Once that search is complete the homicide detectives will take over the investigation.”

We saw police taking armfuls of weapons out of the home of #Brookville triple homicide suspect, 41yo Christopher Snyder. @mcpnews reports he had several previous encounters with police. @fox5dc pic.twitter.com/Isqws2uIIw — Melanie Alnwick (@fox5melanie) May 8, 2018

Police have not released other details about the shooting and what was found in the home. Manger said Snyder’s motive remains under investigation, “but what we do know, from talking to the suspect’s wife, is that she reports that she had been held by her husband over the weekend, and took an opportunity to run out of the house and went into the neighbor’s house, which I think ultimately caused him to go to that neighbor’s house, where killed three people.”

Update – tow trucks arrived to Brookeville triple shooting investigation scene. Escalade removed from suspect’s home; Dodge sedan towed from neighbor’s home pic.twitter.com/AAdiDL8NES — Justin Finch (@JustinNBC4) May 8, 2018

Manger said, “at this point we are not aware of any prior issues between the suspect and these victims.” He said police believe he only went to that home because his wife fled there.

NEW: Online databases list Brookeville, Md. shooter Chris Snyder's home address with two businesses: •Black Widow Enterprises LLC – licensed gun dealer •Identity Solutions Inc – security systems company started 13 years ago ATF on scene due to weaponry + possible explosives. pic.twitter.com/ZeTDIqFP1R — Kevin Lewis (@ABC7Kevin) May 8, 2018

According to ABC 7’s Kevin Lewis, Snyder had two businesses registered at his Brookeville home, Identity Solutions Inc., a security systems company, and Black Widow Enterprises LLC, which was a licensed gun dealer. A website registered by Identity Solutions Inc, digitalidsolutions.com, is not working, but an archive of the site from 2013 exists. The “About Us” section, states, “Identity Solutions is a leader in Information Security and Assurance, Identity and Access Management, PKI, Smart Cards and Biometrics, delivering these solutions to Commerical, Federal, Government and State agencies. Identity Solutions has demonstrated technical depth and leadership on a broad range of initiatives. We have the right people and resources to deliver the ‘total’ product”.”

Another section of the website explains that the company provides security audits, penetration analysis, consulting services and regulatory audits. The site’s contact page lists its address as being a home in Elliott City, Maryland, that public records show Snyder once owned. The founder and president is listed as Chris Vittek, which is one of Snyder’s aliases, according to public records.

3. Snyder, an Air Force Veteran Who Told Neighbors He Worked With a ‘Three-Letter Agency’, Was Arrested Last Year on Drug & Weapon Charges

UPDATE: Multiple fatalities at Brookeville home. Suspect is known to police. It's unclear where that suspect is currently. Residents in the neighborhood are being told to shelter in place. People returning from work, school, errands, etc… being directed to staging area. pic.twitter.com/UK1WnKH5Dr — Kevin Lewis (@ABC7Kevin) May 7, 2018

Public records show that Snyder was arrested in Montgomery County, Maryland, on June 8, 2017, and charged with carrying a concealed dangerous weapon, a misdemeanor. A dangerous weapon is defined as a “dirk knife, bowie knife, switchblade knife, star knife, sandclub, metal knuckles, razor, and nunchaku.” He was also charged with possession of a controlled dangerous substance. Further details about that case were not immediately available. According to WJLA-TV, the arrest was expunged from his record.

Snyder appears to be a native of Wichita Falls, Texas, where his mother still lives. He served in the U.S. Air Force and was once stationed in Alaska, public records show. He also appears to have used the name Christopher Louis Vittek at one point. A speeding ticket in Alaska is the only other thing to show up in a criminal background check.

Today neighbors described Chris Snyder as aggressive, cocky, private and strange – the kind of man you did not want to cross. Snyder was known for keeping his blinds closed + prominently posting security signs in his yard. One such sign warns of “24 hour recorded surveillance.” pic.twitter.com/0PKsrJmSGS — Kevin Lewis (@ABC7Kevin) May 8, 2018

Snyder talked with neighbors about having worked for a government agency at one point, referencing “three letter agencies,” a phrase typically used to reference the FBI, CIA and NSA. But authorities have not confirmed that he had ties to any of those agency or did any kind of secret government work.

Spoke with a farmer named Todd Greenstone today about Christopher Snyder, the gunman police say killed 3 people in Brookeville. Showing me Snyder’s old target, Todd says he was often here at his shooting range. The story on @WTOP pic.twitter.com/wFFAvJxFHI — Melissa Howell (@Mhowell003) May 8, 2018

Todd Greenstone, a farmer who lives in area, told The Washington Post, “he was a nutcase.” Greenstone said he got to know Snyder in recent years after Snyder came to his farm to take part in target shooting with Greenstone’s friends.

“I just didn’t care for the guy,” Greenstone told the newspaper. “We do good, clean, honest shooting, some skeet shooting. He came loaded for bear.” Greenstone told the newspaper Snyder once came to a target shooting session with two guns holstered to his waist and another around his ankle. He also brought “assault-style rifles,” and asked to set up multiple targets. Greenstone said Snyder cryptically talked about working for an agency “with three letters,” but Greenstone said that came across as “nonsense,” The Post reports.

Other neighbors told WUSA-TV that Snyder boasted about his military service and claimed to have taken part in overseas operations. Neither WUSA nor Heavy have been able to confirm details about Snyder’s military career. He also claimed to be “special ops” and told neighbors he could protect them if anything ever happened, according to WBFF-TV.

Neighbors say Chris Snyder was "cocky and arrogant" neighbor Becky Sisson recalls a time he told her, "I was special ops, if anything happens here I will protect you." Police say Snyder chased his wife to a neighbor's home and killed 3 innocent people. — Joy Lambert (@JoyLambert) May 8, 2018

“It always looked like he was wearing a bulletproof vest, had a cap on, always had sunglasses on, driving a dark-stealthy car,” neighbor Becky Sisson told reporters, according to WJLA-TV. “We all pretty much knew to stay away from this guy. He was just, we knew that his ducks weren’t all lining up. Something was off with him.”

Today neighbors described Chris Snyder as aggressive, cocky, private and strange – the kind of man you did not want to cross. Snyder was known for keeping his blinds closed + prominently posting security signs in his yard. One such sign warns of “24 hour recorded surveillance.” pic.twitter.com/0PKsrJmSGS — Kevin Lewis (@ABC7Kevin) May 8, 2018

Greenstone also talked to WTOP-TV, telling them Snyder treated the shooting outing as a tactical exercise. “He was acting like a military killer,” Greenstone told the news station. “We just felt that he was dangerous.” Greenstone showed the news station an old car part that Snyder shot at, with bullet holes in it. “A normal gun will not shoot through that steel. He was using armor-piercing ammunition,” he said.

“I asked him not to come back to the farm,” Greenstone told The Post.

4. He Bought the Brookeville Home in 2013 for $800,000 & Appears to Have Been Running a Gym Called ‘Code 3 Tactical Academy,’ Where He Trained Local Police Officers

Mulitiple people shot to death inside Md. homePolice say multiple people have been shot and killed inside a home in Brookeville. 2018-05-07T22:27:08.000Z

Snyder bought the home at 22001 Brown Farm Way in Brookeville for $800,000 in 2013, public records show. He previously lived in Elliott City, in Howard County, and he sold his home there when he bought the Brookeville home. Records show that he used a Veterans Affairs loan program to purchase the house.

Kareem Alalfey told The Washington Post he has known Snyder for several years. Alalfey said he was shocked by the killings and told the newspaper, “I knew he was going through some things, but he always handled himself well. It’s hard for me to even wrap my head around what happened.”

Alalfey told The Post that Snyder was associated with Code 3 Tactical Academy, a Columbia, Maryland, gym that teaches self defense tactics. Alalfey told the newspaper Snyder was well known there and it was common to see Snyder laughing and joking with patrons. The gym specializes in “Spartan Defense Tactics,” a special program created by the gym’s top trainer, who appears to be Snyder.

In a Facebook video for the gym, a person named Chris Smith is listed as the owner of Code 3 Tactical Academy, which teaches Muay Thai, along with other martial arts, women’s defense and trains current and former military and law enforcement personnel, including local officers according to its website. Chris Smith is an apparent pseudonym for Chris Snyder.

In the Facebook video, Snyder says, “My grandfather got me into Kenpo karate when I was six and then he got me into judo. He was a 22-year Army veteran so that was their background back in the day on the judo side of it. Self defense is taking those styles and bringing them in and utilizing that stuff that inflicts the pain needed to get away from a situation.”

Snyder added, “I’ve trained military, I’ve done the private military contracting for 15, 16, years, federal government, DOD side of it. … Is it my duty as a human to help another human? And that’s what I believe in and that’s what I teach people.”

A woman who describes herself on social media as a Muai Thai instructor at Code 3 Tactical Academy lists Chris Smith as her husband on Facebook, but has Snyder in her last name. She could not be reached for comment by Heavy. According to her social media profiles, the woman is a top-ranked Muay Thai master and has worked with UFC and other top MMA stars to help in their training.

The gym’s website includes a testimonial from Deputy W. Daniels of the Howard County, Maryland, sheriff’s office:

I have been in law enforcement for over 28 years and have been to a lot of defensive tactics training over the years. Some was really good and useful and some were more involved and harder to become proficient without a lot of practice. In a short amount of time training with Chris, I learned just a couple of techniques that I was able to almost immediately able to use in real life situations; in a courthouse setting and on the street. The techniques I learned were very simple and efficient and didn’t have many steps to remember like others we have been through. The techniques were very organic in that they utilize knowledge of the human body and physiology to quickly enable you to gain control or compliance of your subject before they know what’s happening. The techniques are not overly violent and provide you with options and alternatives off the initial moves that you can easily utilize. People of any size and level of ability can utilize these techniques with a minimal amount of instruction. I’m recommending Spartan Defense Tactics to my agency as a part of our in-service training program.

The gym’s Facebook page shows Chris, its owner, training with police officers from other local police departments, including the Anne Arundel County Police, and with members of a local ambulance crew.

“Spartan Defense Tactics is a defense system that is true to its nature. We do not teach sport, we teach self defense. There is no belt system here, or any competition rules you need to abide by. This is self defense and we offer real life scenarios to simulate what you could encounter,” the gym’s website states. “They say train for worst case scenarios so that when the time comes you are calm, confident and proficient. This is what we live for, helping others feel confident and assured they can handle themselves. We do not breed warmongers, we mold proficient men and women that know how to avoid fights first and foremost, and how to defend themselves if they must.”

The gym’s owner is named in documents online is Keith Lynn, a former police officer and correctional who also runs Code 3 Security & Protection Services Inc., a company based in Hanover, Maryland. Lynn was a guard at a maximum security prison from 1992 to 2002 and then worked as a Washington D.C. Metropolitan Police officer.

“Chris S.,” is listed on the Code 3 website as being its COO. His biography states, “Mr. Chris S. has over 22 years in security including military and as a private security contractor. He has worked in many capacities in the security arena to include, but not limited to, PSS, EP, FP, mobile security, security advisor, building training programs, business development, and working in a variety of senior management positions. He is the Chief Instructor for Code 3 Tactical Academy.”

Former colleague of Chris Snyder says he was aggressive, extremely paranoid and very controlling. Describes him as a “ticking time bomb” Snyder took his own life after police say he killed 3 people in Brookeville, MD on Monday. Our story airs at 4,5&6 @nbcwashington pic.twitter.com/MDcVQca5m7 — Meagan Fitzgerald (@MeaganNBCDC) May 9, 2018

A man who once worked with Snyder told WRC-TV that Snyder was “high strung, unstable and a habitual liar.” The former co-worker said he believed Snyder’s security clearance went into delay status in 2013 after they worked together for about a year, the news station reports. He said Snyder was “obsessed with being a tough guy” and was a “con man,” according to WRC.

5. Snyder Filed for Divorce From His Ex-Wife in 2017 & Said in Court Documents the Case Should Be Sealed Because of ‘Classified’ Operations He Worked On

Multiple fatalities in Brookeville shootingMontgomery County police are investigating reports of multiple people found shot in a house in Brookeville. Subscribe to WBAL on YouTube now for more:http://bit.ly/1oJSRCN Get more Baltimore news: http://wbaltv.com Like us: http://facebook.com/wbaltv11 Follow us: https://twitter.com/wbaltv11 Google+: https://plus.google.com/+wbaltv11 2018-05-08T02:28:41.000Z

Chris Snyder filed for divorce from his ex-wife, whose name is being withheld by Heavy, in February 2017, Maryland court records show. The case, filed in Howard County family court, was closed in May 2017. In the records, Snyder is listed as the plaintiff and his wife as the defendant. Snyder hired an attorney, while his wife represented herself.

In court documents, Snyder argued that his divorce records should be sealed because he was an Armed Forces veteran who had served on “many operations that remain classified,” and keeping the file public could put him or his family at risk, according to The Washington Post. Snyder also wrote that he was still a government contractor with top secret security clearance and attached letters showing he worked as a contractor for local law enforcement agencies, performing training and other work. The Post said the claims could not be immediately verified, but the court did agree to remove identifying info such as his address and phone number.

He wrote at the time he was still a government contractor and maintained a top secret security clearance. Snyder attached letters that showed he purportedly contracted for local law enforcement agencies, performing training and other work. The claims in the file could not be immediately verified, but the court agreed to seal his identifying information such as address and phone number.

According to The Post, Snyder had remarried and the woman named in the divorce records was not the same woman who was involved in the domestic disturbance this week. It is not clear how long Snyder and his second wife were married. The woman named in the 2017 court documents could not be reached for comment by Heavy and hung up the phone when contacted by The Post.

Mary Olson, Snyder’s neighbor who was killed in the shooting, let his wife into her home to try to help her, Olson’s sister, Louise Tano, told The Post. “She tried to speak to the gunman and calm him down,” Tano told the newspaper. “Mary would do anything in the service of others. She didn’t hesitate a second to protect this woman in need.”