A San Francisco jury has convicted a tech entrepreneur on charges of second-degree murder in the stabbing death of Bob Lee, the founder of mobile payment service Cash App.

Nima Momeni, 40, faces a sentence of 15 years to life in prison for the killing.

Mr Lee, 43, was killed in the early morning hours of 4 April 2023.

Police found him unconscious in the Rincon Hill neighbourhood with two stab wounds to his chest. He died later in hospital.

Momeni was found not guilty of the more serious charge of first-degree murder, which denotes a pre-meditated killing.

Jurors deliberated for seven days before announcing they had reached a verdict.

Following the conviction, Mr Lee's brother Oliver Lee said his family was "happy with the result".

"We're happy that Nima Momeni won't be on the streets, no longer has the opportunity to harm anyone else in this world," he said.

According to prosecutors, Momeni stabbed Mr Lee because he was upset that he had introduced his sister, Khazar Momeni, to a man who gave her GHB, a so-called date rape drug.

Like the prosecution, Nima Momeni's defence team said he had been partying with his sister and Mr Lee on the night of his murder. But they said Momeni had been acting in self-defence.

Mr Lee, Momeni said, had lunged at him with a knife over what Momeni described as a "bad joke", according to the San Francisco Chronicle.

Autopsy reports indicated that Mr Lee was under the influence of alcohol, ketamine and cocaine at the time of his death. Defence attorneys argued that a pattern of drug use had made Mr Lee aggressive.

"We are victims of drug abuse," Momeni's mother, Mahnaz Tayarani, told reporters outside the courtoom on Tuesday. "I know my son... This is not a fair trial."

The incident had stoked fears over crime and safety in the Bay Area, with tech billionaire and Donald Trump ally Elon Musk saying at the time that "violent crime in SF is horrific".

While praising the conviction on Tuesday, San Francisco District Attorney Brooke Jenkins took direct aim at Mr Musk, saying he had tried to shame the city and make the case "seem like lawlessness in San Francisco".

"We knew it was something different," she said.