Man interested in coworker kills her fiancé to eliminate competition, police say

DALY CITY, Calif. — A security officer at the San Francisco International Airport who wanted to date a coworker is accused of killing the woman’s fiancé to get him out of the way, police investigators said.

Kevin Prasad, 31, of South San Francisco, is accused of fatally shooting Mark Mangaccat on April 25, according to the San Mateo Daily Journal. Records from the San Mateo County Jail show that he is charged with first-degree murder with special circumstances, attempted murder, assault with a firearm and conspiracy to commit a crime.

The special circumstances are that Prasad lay in wait, the records show. Prasad’s friend, Donovan Matthew Rivera, 25, of Hayward, is accused of helping Prasad.

Rivera is charged with murder with special circumstances and conspiracy to commit a crime. Both men are being held without bond.

The Daily Journal reported that Prasad worked at the airport with Mangaccat's fiancée, identified by CBS San Francisco as Thandel Seinn. Investigators said that Prasad was interested in a romantic relationship with Seinn and had encouraged her to break up with Mangaccat, but she turned him down.

Mangaccat went to the airport the day of the shooting to pick up Seinn, who had worked her last shift as a security officer. CBS San Francisco reported that the couple planned to move to Las Vegas with their 3-year-old daughter.

An unhappy Prasad decided to do something about those plans, San Mateo County District Attorney Steve Wagstaffe told the Daily Journal.

"The working proposition for the motive is, 'If I kill him and get him out of the way, then I could be there to start the relationship with the grieving widow,'" Wagstaffe told the newspaper. "That's pretty bizarre."

Investigators said that Mangaccat drove up to his family’s home in Daly City, which is located about 10 miles south of San Francisco, and was backing his car into the garage when Prasad walked up the driveway and fired five to six shots into the vehicle, killing him. Seinn was not struck by any of the bullets.

Prasad ran back to the getaway car, which was driven by Rivera, and they fled the scene, Wagstaffe told the Daily Journal.

The Washington Post reported that Seinn, who never felt that Prasad was a danger, initially had no idea who might have killed her fiancé. She did not recognize him during the shooting because he was allegedly wearing a hoodie, investigators said.

Wagstaff told the Post that Seinn was in the middle of an interview with detectives when a thought struck her.

"Wait, there's a guy at work who's been trying to date me," she told the investigators, according to the district attorney.

That tip ultimately led to both Prasad and Rivera, who were arrested the day after the homicide.

Seinn told CBS San Francisco that she never dreamed that Prasad's crush on her would have such deadly consequences. The distraught woman said she never took his overtures seriously.

“He just tell me, ‘Don’t go’ and “I want to be with you,’” Seinn said. “He would just say something like a friendly joke.”

She said she considered him a friend.

“At the airport, we work in same job,” Seinn said. “(My) boyfriend, me and him, we were friends.”

Wagstaffe said the relationship remained amicable even on Seinn’s last day at work. Mangaccat previously worked at the airport as well, but left his job after suffering an injury.

Those who knew Mangaccat expressed disbelief on social media at the news of his death.

“He was one of the nicest people,” wrote Jose Chavez, who described Mangaccat as a driver at the airport for VIP passengers flying on United Airlines. “I still can’t believe it. Tell your loved ones you love them, you never know.”

Liza Erpelo described Mangaccat as an “incredibly soft-spoken” person who nevertheless made a huge impact on those who knew him.

Seinn told CBS San Francisco that she is heartbroken.

"I'm crying and I'm thinking, 'What happened?'" Seinn said. "He has no enemies. I don't have enemies, either.

“I didn’t want to lose my husband. He was my soulmate.”

Cox Media Group