Nima Momeni, the Bay Area tech entrepreneur accused of fatally stabbing Cash App founder and crypto executive Bob Lee in San Francisco, is being held on suicide watch as he sits in a California jail cell awaiting his next court date, according to his attorney.

But it's standard operating procedure, not because he's exhibited any warning signs, she told Fox News Digital Wednesday.

"San Francisco County Jail treats ALL people with no criminal history arrested in high-profile cases as suicide risks," Momeni's defense attorney, Paula Canny, wrote in an email from Paris. "It’s not unique to Nima. It’s SOP."

Her brother appeared on Momeni's behalf at his first court date last week because she was traveling. The suspect's arraignment is scheduled for April 25.

CASH APP'S BOB LEE VISITED SUSPECT'S SISTER HOURS BEFORE MURDER. ARGUED WITH ALLEGED KILLER, COURT DOCS REVEAL

Momeni Lee split

Nima Momeni, left, is jailed in San Francisco on a murder charge in the stabbing death of Cash App founder Bob Lee. San Francisco Police say the two knew each other. (Nima Momeni/LinkedIn, Bob Lee/Facebook)

Fox News was in the courtroom last week as Momeni made his first court appearance, wearing an orange jail sweatshirt and pants, a black coronavirus mask and shackles around his ankles. He did not enter a plea and was scheduled for an April 25 arraignment.

He said little, only speaking in response to a question from the judge, saying, "Yes, your honor."

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Momeni's sister, Khazar Momeni, and her husband, Dr. Dino Elyassnia, were at the courthouse for the proceedings.

Lee met with his suspected killer's sister hours before his death, according to court documents, which allege that investigators pieced together the crime in part by reviewing text messages exchanged between Lee and Khazar.

In one conversation, she reportedly told the tech titan that he "handled himself with class" after her brother allegedly "came wayyyyyy down hard" on him.

BOB LEE MURDER: SAN FRANCISCO POLICE SEARCHED LUXURY BUILDING WHERE SUSPECT'S SISTER OWNS CONDO, REPORT SAYS

Khazar Momeni in a portrait

Khazar Momeni, the sister of stabbing suspect Nima Momeni, reportedly exchanged text messages with victim Bob Lee, according to court documents. (Vincent Gotti Photography)

A witness told police Momeni was grilling Lee in his hotel room about "whether his sister was doing drugs or anything inappropriate."

The court filings unveiled Friday also reveal that police recovered the suspected murder weapon, a bloody 4-inch kitchen knife discarded near the crime scene.

Bob Lee poses with his children

Cash App founder and tech exec Bob Lee, 43, was a father of two. He had recently moved from San Francisco to Miami due to a concern in public safety issues. (Bob Lee/Facebook )

And they said they found surveillance video showing Lee and Momeni leaving the sister's apartment, getting into a car and driving to a location near where Lee was later found with three stab wounds.

Police arrested Momeni last week at his Emeryville home, across the Bay Bridge from where Lee called 911 begging for help after he was stabbed three times April 4.

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Momeni lived and had an office there for his outsourcing firm, Expand-IT, according to police.

A former employee told Fox News Digital Momeni was "the cool guy at times" but could also be "wild and erratic."