Matt Dorsey, the Democratic San Francisco city supervisor who represents Rincon Hill, a neighborhood near the Bay Bridge, condos and corporate offices, said on Twitter that Mr. Lee’s death was “a senseless tragedy that I know is made worse by the fact that no suspect is yet in custody.”

Before Mr. Lee joined MobileCoin in 2021, he was the chief technology officer of the payment company Square, which was renamed Block in 2021, and was a software engineer at Google. He was also a start-up adviser and had invested in companies including SpaceX and Clubhouse, according to his LinkedIn.

Mr. Dorsey, the San Francisco supervisor, said that he had been speaking with the police about the investigation into the stabbing since Tuesday morning. No arrests have been made in what is being called a homicide by the police.

“I’ve also heard from many constituents in the area — some of whom have already voiced concerns to me about public safety challenges — and I’m asking everyone to cooperate with police in their investigation, especially those with access to surveillance video that may help,” Mr. Dorsey said.

At the time of his death, Mr. Lee, 43, was the chief product officer of MobileCoin, a cryptocurrency start-up. The founder and chief executive of MobileCoin, Joshua Goldbard, confirmed in an emailed statement that Mr. Lee died on Tuesday but did not give a cause.