The shooter opened fire at the Prince Law Group office in Summerlin during a deposition of his son, whom he had been representing, the sources said Monday afternoon.
The other lawyer was representing his own wife, who was the former daughter-in-law of the shooter and opposing counsel, the sources said.
The alleged gunman died after he turned the gun on himself, according to the sources. His son survived.
The sources characterized the shooting as targeted and domestic-related.
The incident occurred about 10 a.m. at the fifth-floor law office on West Charleston Boulevard near Pavilion Center Drive, Clark County Sheriff Kevin McMahill said at a news conference. Responding officers found the three people with gunshot wounds, police said Tuesday. They were pronounced dead at the scene by medical personnel.
“The suspect was not killed by my police. We believe he took his own life,” he said, adding that there was no further threat to the public.
The Clark County Coroner’s Office on Tuesday identified the deceased people as Ashley Prince, 30; Dennis Prince, 57 and Joseph Houston, 77.
The coroner has not released the cause and manner in their deaths.
Robert Eglet told NBC News that the attorney who was slain was his former law partner and that they had known each other for 30 years. The pair “were close friends for a very, very long time,” Eglet said.
“He was a very good guy. He was one of the finest trial lawyers in the state of Nevada. It’s tragic, and it’s senseless,” he said.
Eglet said his friend specialized in medical malpractice cases.
There are businesses adjacent to the law office where the shooting occurred, McMahill said. First responders evacuated the building and followed an active-shooter protocol, officials said. Hundreds of people were evacuated, police said.
The suspect’s vehicle was being investigated, McMahill said, adding that police were trying to shore up a motive.
“We have a theory at this point, but I cannot release any of that information until we’ve confirmed that information,” he said.
A law office on the fifth floor did not answer a call seeking comment Monday afternoon. Police said they were using nearby Red Rock Casino as an assistance center.
If you or someone you know is in crisis, call or text 988 to reach the Suicide and Crisis Lifeline or chat live at 988lifeline.org. You can also visit SpeakingOfSuicide.com/resources for additional support.
This article was originally published on NBCNews.com