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Prosecutors say Bob Lee’s fatal stabbing was ‘planned’ and a witness overheard him arguing with the suspect about his sister

Tristan Bove
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Tristan Bove
Tristan Bove
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Tristan Bove
By
Tristan Bove
Tristan Bove
Down Arrow Button Icon
April 14, 2023, 5:43 PM ET
Mayor London Breed provides updates on Cash App founder Bob Lee’s homicide investigation at the San Francisco Police Department with District Attorney Brooke Jenkins (right) and Police Chief William Scott (left), April 13, 2023.
Mayor London Breed provides updates on Cash App founder Bob Lee’s homicide investigation at the San Francisco Police Department with District Attorney Brooke Jenkins (right) and Police Chief William Scott (left), April 13, 2023.Tayfun Coskun—Anadolu Agency/Getty Images

The fatal stabbing of Silicon Valley executive Bob Lee with a kitchen knife on a downtown San Francisco street last week followed a night of socializing with friends, including the sister of the IT entrepreneur accused of murdering him, local prosecutors said in a court filing.

San Francisco District Attorney Brooke Jenkins urged a state judge not to grant bail and release suspect Nima Momeni, saying the slaying was “planned and deliberate” and that “detention is necessary to protect public safety.”

New details in Friday’s filing reveal more about events in the hours leading up to the slaying of Lee, 43, who created the mobile payment service CashApp and was revered in the tech world for his coding talents.

A unidentified person who was having drinks with Lee and Momeni’s younger sister on the eve of the killing told investigators he overheard a FaceTime call in which Lee was questioned by Momeni over whether his interaction with the sister involved drugs or anything inappropriate. The witness said the sister may have been in a troubled marriage, according to the filing. Hours later, surveillance footage showed Momeni and Lee leaving the Millennium Tower apartment building, where the sister lives, in Momeni’s BMW Z4 sports car.

Momeni drove in the opposite direction of Lee’s hotel to a dark and secluded area a few blocks away, where both men exited the car, prosecutors said, citing camera footage in the filing. In the next five minutes, Momeni stabbed Lee three times with a kitchen knife, including one wound that “directly penetrated his heart, causing his death,” before speeding away, according to the filing.

“Defendant did not use some kind of pocket knife, but a cooking knife from an apartment and kitchen,” Jenkins wrote. “This was a planned and deliberate attack.”

When police officers responded to the scene at about 2:35 am, they found the “victim uncontrollably bleeding from apparent stab wounds to his chest and hip,” according to the filing.

Police found blood splattered on the sidewalks and a silver knife with a black blade about 4 inches long, with “what appeared to be blood on it” near the 400 block of Main Street, not far from Millennium Tower, prosecutors said.

Investigators unlocked Lee’s phone this week and found a message on Lee’s phone from Momeni’s sister saying, “Just wanted to make sure your doing ok Cause I know nima came wayyyyyy down hard on you And thank you for being such a classy man handling it with class.”

On Thursday, San Francisco Police Chief Bill Scott had said at a news conference while announcing Momeni’s arrest in the nearby city of Emeryville that the two men knew each other, but declined to provide details on the alleged motive behind the fatal attack. Media reports had speculated in the immediate aftermath of Lee’s death that the slaying was an act of random street violence.

“This has nothing to do with San Francisco,” Scott told reporters. “This had to do with human nature.”

On Friday morning, Momeni, the 38-year-old owner of a small IT firm, made his first court appearance to push back the date to enter his plea.

Momeni, who is in custody, appeared briefly in a San Francisco courtroom to ask to delay his arraignment until April 25 because the lawyer handling his case is on vacation. The judge granted the request.

Momeni wore an orange sweatshirt and spoke only to acknowledge his lawyer’s request for the delay. Members of his family were also in the courtroom.

Lee was the first chief technology officer of Square, the startup co-founded by Jack Dorsey, and now called Block Inc. While at the company, he created CashApp, a money transfer tool that lets users buy stocks and Bitcoin. Earlier in his career, he helped develop Android while working as a software engineer for Google.

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Tristan Bove
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