By Dan Whitcomb

(Reuters) – The tech executive charged with stabbing Cash App founder Bob Lee to death in San Francisco confronted him earlier in the evening about his ties to the suspect’s younger sister, prosecutors said on Friday in court documents that outlined a possible motive.

Nima Momeni, 38, was arrested on Thursday and charged with the April 4 murder of Lee, who was found stumbling through the city early that morning bleeding from three stab wounds. He later died at a nearby hospital.

Momeni, founder of the Bay Area software company Expand IT, briefly appeared in a San Francisco courtroom on Friday, where a judge postponed his arraignment until April 25. Momeni was ordered held without bail until then.

San Francisco prosecutors, who called the murder “planned and deliberate” in court papers filed for the hearing, wrote that a close friend of Lee, identified only as “Witness 1”, described spending time with the Cash App founder, Momeni and Momeni’s younger sister on the day before the murder.

Witness 1 told investigators that on that afternoon Momeni questioned Lee, 43, over whether his sister was “doing drugs or anything inappropriate,” according to the documents. The friend said Lee assured him that nothing of the sort had taken place.

Investigators who gained access to Lee’s phones following his death discovered a FaceTime call between him and Momeni’s sister, who is not identified by name in the court papers.

They also found a text message from the sister reading: “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 Love you Selfish pricks.”

Witness 1 said it was not clear to him whether Lee had engaged in an intimate relationship with Momeni’s sister, who is married but whose relationship to her husband was described as “in jeopardy.”

The sister and her husband both attended Momeni’s court hearing on Friday.

Surveillance camera footage shows Momeni arriving at his sister’s apartment at 8:31 p.m. on April 3, the court documents said, followed by Lee roughly four hours later. The cameras captured both men leaving the apartment some 30 minutes before the murder.

The two men are seen in camera footage driving to a remote area where prosecutors believe that the stabbing took place.

Block Inc-owned Cash App allows users to transfer money through a mobile application, which the company touts as an alternative to traditional banking services.

(Reporting by Dan Whitcomb; Editing by Cynthia Osterman)

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