A Maryland software developer was asleep in his bedroom when police opened fire from outside the house and shot him dead, according to his family.

The Montgomery County Police Department said in a news release Friday that Duncan Socrates Lemp, 21, “confronted” police who were executing a “high risk” search warrant at the Potomac home early Thursday. They said a tactical unit member fatally shot Lemp around 4:30 a.m.

According to police, the officers were “following up on a complaint from the public that Lemp, though prohibited, was in possession of firearms.”

However, Rene Sandler, an attorney for Lemp’s family, said an eyewitness gave a “completely contrary” account of the shooting. She said police have “absolutely no justification” for shooting Lemp as far as she can tell.

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“There is no warrant or other justification that would ever allow for that unless there is an imminent threat, which there was not,” she told The Associated Press.

Duncan Lemp and his girlfriend were shot without warning, the family says

Sandler said Lemp’s family believes the officers opened fire with shotguns, including through Lemp’s bedroom window, while he and his girlfriend were sleeping. Nobody in the home, which Lemp shared with his parents and 19-year-old brother, heard any warnings or commands beforehand, she said.

Lemp’s girlfriend was also wounded in the shooting. Detectives later recovered three rifles and two handguns from the house, police said.

A police spokesman did not immediately respond to requests for comment by The AP or Pluralist. Officers are not required to alert targets of “no-knock warrants,” which judges issue to protect police or evidence.

In a statement released Friday by their lawyers, Lemp’s family said the warrant that police obtained to search the home makes no mention of any “imminent threat” to law enforcement or the public.

“Any attempt by the police to shift responsibility onto Duncan or his family, who were sleeping when the police fired shots into their home, is not supported by the facts,” they said.

The relatives said neither Lemp nor anyone else in the home had a criminal record. They pledged to “hold each and every person responsible for his death.”

“We believe that the body camera footage and other forensic evidence from this event will support what Duncan’s family already knows, that he was murdered,” they said.

Montgomery County police said prosecutors from neighboring Howard County will review “the facts and circumstances of the encounter.” The counties have agreed to review each other’s officer-involved shootings in cases of injury or death.

The officer who killed Lemp was placed on administrative leave, which is standard procedure in police shootings.

“He was pro-America”

Friends and coworkers told The AP Lemp worked as a software developer and was trying to raise money for a startup company.

“He was a talented, smart guy. Super nice. Didn’t deserve to get shot,” said Samuel Reid, whose Canadian software company employed Lemp as an independent contractor.

On an internet forum called “My Militia,” someone who identified himself as Duncan Lemp of Potomac said he was “an active III%’r and looking for local members & recruits.” The username of the person was “YungQuant,” which friends told The AP Lemp used on social media.

The Three Percenters, whose logo is the Roman numeral III, are a wing of the militia movement.

The AP reported that Lemp recently shared a photograph to “My Militia”of two people holding up rifles. The post included the word “boogaloo,” which refers to a future U.S. civil war.

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Friends said they never heard Lemp espouse any anti-government rhetoric. Sandler said Lemp was not a part of any anti-government or militia-type group.

“He was pro-America and supported wholeheartedly all the protections of the Constitution,” she said.

One of Lemp’s friends, Tsolmondorj Natsagdorj, 24, of Fairfax, Virginia, said they had liked to talk about cryptocurrency and sometimes politics. He described Lemp as a libertarian who frequented Reddit and 4chan.

“Duncan was a young guy with a bright future as an entrepreneur,” Natsagdorj said. “He was working on things to change the world.”