Bay Area man charged with killing wife, mother-in-law also charged in 2024 Los Angeles County murder; mistress linked to each killing

By Carlos E. Castañeda

A Bay Area man charged last year with murdering his wife and mother-in-law is now being charged in a 2024 Los Angeles County murder, with his mistress connected to all three killings, prosecutors said.

Howard Wang, 43, was arrested on Sept. 19, 2025, a day after his wife, Linlin Guo, and mother-in-law, Beimin Cheng, were found dead in Wang’s Walnut Creek home. Police said Wang had slashed their throats and concocted a story about arriving home and shooting at a fleeing intruder responsible for the killings. Sources told CBS News Bay Area another adult and two children were inside the home at the time, but they were not hurt 

On Sept. 30, 2025, 45-year-old Yan Wang, who is not related to Howard Wang, was arrested and charged with being an accessory after the fact. The Contra Costa District Attorney’s Office said Yan Wang was Howard Wang’s mistress at the time of the murders and attempted to help him avoid arrest. Prosecutors allege that on the day of the murders, Yan Wang destroyed cellphones to prevent evidence from being produced, and broke into the home of Howard Wang and Linlin Guo the day after the murders to steal other evidence.

On Monday, the Contra Costa DA’s Office said in a press release that Howard Wang now faces an additional murder charge for the June 2024 killing of 41-year-old Chengli Li in Los Angeles County. Li, who was found shot to death outside his apartment in San Gabriel, was Yan Wang’s boyfriend at the time, according to the DA’s Office.

Both Howard Wang and a second suspect, 33-year-old Demarques James Pearl of Los Angeles, were charged in Li’s murder. According to the DA’s Office, Wang and Pearl planned the murder before traveling from the Bay Area to Los Angeles County on June 7, 2024, and killed him the next day. A Los Angeles County Sheriff call log indicated Li was shot and killed at about 1:35 a.m. on the 100 block of Walnut Grove Avenue in San Gabriel.

It was not clear whether Yan Wang was aware of Howard Wang’s alleged involvement with Chengli Li’s murder.

Li’s murder in San Gabriel will be joined with the Walnut Creek double murders to be prosecuted in Contra Costa County, the DA’s Office said. 

Howard Wang and Pearl were scheduled to be arraigned on Monday in Martinez, but after defense attorneys asked the court to reschedule the arraignments. Pearl will now be arraigned on April 1 and Wang on April 14 in Martinez.