FBI raids Oakland Mayor Sheng Thao's home, several other locations: source

Oakland Mayor Sheng Thao's home was among four locations raided by the FBI Thursday morning, a source told ABC7 News.

OAKLAND, Calif. (KGO) -- A home associated with Oakland Mayor Sheng Thao was among several locations raided by the FBI Thursday morning, a source confirms to ABC7 News.

The FBI provided this statement Thursday morning:

"The FBI is conducting court authorized law enforcement activity on Maiden Lane. We are unable to provide additional information at this time."

The details of the FBI's investigation remain unknown, but sources say the case involves the IRS and the US Postal Service.

Confirmed locations raided by federal officials:

Home of Mayor Sheng Thao on Maiden Lane

California Waste Solutions at the Embarcadero

Home of California Waste Solutions' Andy Duong on View Crest Court

Home of California Waste Solutions' David and Linda Duong on Skyline Blvd

Mayor Thao's home that was being investigated is on Maiden Lane in the Oakland Hills.

A neighbor visiting from San Diego told ABC7 News that she was woken up by law enforcement banging on her door around 6 a.m.

ABC7 News insider Phil Matier says that according to a law enforcement source, the location is one of four homes in Oakland where warrants have been issued and served.

An ABC7 News crew on scene said there were several unmarked vehicles at the house and agents were seen carrying boxes from the location.

Mayor Thao was supposed to appear at an event Thursday morning at 10 a.m., but she has canceled.

Among the other locations raided is the home of Andy Duong of California Waste Solutions, who helped organize Mayor Thao's trip to Vietnam last year.

Andy Duong is the son of David Duong, the President and CEO of California Waste Solutions, whose house was also raided.

California Waste Solutions is Oakland's garbage vendor.

This comes as recall organizers have called on Thao to resign as mayor. The recall effort has gotten enough signatures to appear on a ballot.

Stay with ABC7 News for updates on this developing story.