A “force of nature” tech entrepreneur who founded a multibillion-dollar payments service has been stabbed to death.
Bob Lee, 43, was attacked in San Francisco on Tuesday morning local time and later died in hospital.
His father, Richard, said he had “just lost my best friend” in a tribute on Facebook confirming the news.
“Bobby worked harder than anyone and was the smartest person I have ever known,” he said.
“He will be missed by all those that knew him. Thank you to those who have reached out in support.”
Police had not named the victim and said an investigation into the killing was ongoing, with no arrests made.
Sky News’ US partner network NBC News reported that Bob and Richard Lee both lived in Miami, Florida, having grown closer since the death of Bob’s mother in 2019.
It was not clear why the victim was back in San Francisco.
What is Cash App?
Similar to PayPal, Cash App lets users transfer money through a smartphone app.
The company, which has been valued at $40bn (£32bn) by Forbes, says it’s an alternative to traditional banking.
Parent company Block said it had more than 50 million monthly active customers as of 31 December 2022.
Lee ‘instrumental’ on fintech scene
Lee was working as chief product officer at cryptocurrency firm MobileCoin when he died.
Founder Joshua Goldbard said Lee was “a force of nature”.
“He was made for the world that is being born right now, he was a child of dreams, and whatever he imagined, no matter how crazy, he made real,” he added.
Lee was previously chief tech officer at Square, the fintech start-up co-founded by former Twitter boss Jack Dorsey, which later became Block.
Dorsey called Lee’s death “heartbreaking”, hailing him as “instrumental” to Square and Cash App.
He also helped build the Android mobile operating system, according to Lee’s Twitter and LinkedIn pages.
Musk: Crime ‘horrific’ in San Francisco
Musk tweeted he was “very sorry” to hear of Lee’s death.
“Many people I know have been severely assaulted,” said the billionaire.
“Violent crime in SF is horrific and even if attackers are caught, they are often released immediately.”
In the same period last year, there were 10.
Away from business, Lee helped the World Health Organization (WHO) build its COVID-19 app.
The WHO told NBC News he offered “support and expertise” and “built a large part of the server” for the app.
Lee’s ex-wife Krista Lee also paid tribute, describing him as “everyone’s best friend”.
They had two children together, 17-year-old Damien and 14-year-old Scout.