Suspect allegedly drove Bob Lee to dark area, stabbed him 3 times with kitchen knife

A fellow tech executive killed 43-year-old Cash App founder Bob Lee earlier this month with a kitchen knife after driving him to a secluded area, prosecutors said in a court filing Friday.

Police arrested the suspect on Thursday and identified him as Nima Momeni, 38, who appears to be the owner of an Emeryville, California-based company called Expand IT.

In a motion filed on Friday to hold Momeni without bail, prosecutors offered new details about the events leading up to the alleged murder.

Lee, an executive at cryptocurrency firm MobileCoin, was killed in the early morning hours on April 4 in the San Francisco neighborhood of Rincon Hill, the San Francisco Police Department said last week.

During the previous afternoon, Lee spent time with Momeni's sister and a witness, who identified him or herself as a close friend of Lee, prosecutors said.

Later in the day, at Lee's hotel room, he had a conversation with Momeni in which he asked Lee about whether his sister was "doing drugs or anything inappropriate," the witness told the police, according to the document.

Lee reassured Momeni that nothing inappropriate had taken place, the witness said to police.

Early the following morning, at about 2 a.m., camera footage showed Lee and Momeni leaving Lee's hotel and getting into Momeni's car, a BMW Z4, prosecutors said.

Video shows the BMW drive to a secluded and dark area where the two men got out of the car. Momeni "moved toward" Lee and the BMW drove away from the scene at high speed, according to the court document.

Police later found a roughly 4-inch blade at the scene that appeared to have blood on it, the document said.

The doctor who conducted the autopsy found that Lee had been stabbed three times, including one strike that penetrated his heart, the document said.

"Mr. Momeni was taken into custody without incident in Emeryville and transported to San Francisco County jail and booked on a charge of murder," San Francisco Police Chief William Scott said at a briefing on Thursday. "Our investigators have been working tirelessly to make this arrest."

San Francisco District Attorney Brooke Jenkins on Thursday applauded the efforts of the SFPD.

"While in some cases we do immediately have as suspect, that was not the situation here," she said. "Mr. Lee's killer has been identified, arrested, and now will be brought to justice."

"He positively affected millions of people throughout his life. He had an overarching need to make technology accessible, and to help out everyone," Bob Lee's brother Timothy Oliver Lee said in a statement Thursday. "Bob's dream was to make technology free and available."

"Every day around the world, people interact with technology that Bob helped create. Bob will live on through these interactions and his dreams of improving all of our lives," Timothy Oliver Lee's statement continued. "As a family, we're very thankful to the hard working Detectives at the SFPD for bringing his killer to Justice."

London Breed, the mayor of San Francisco, said in a statement to ABC News last week that Lee's death marks a "horrible tragedy."