Federal law enforcement officials on Thursday were executing search warrants at the offices of bankrupt solar company Solyndra in California, an FBI spokeswoman said.

We are executing search warrants at Solyndra regarding a joint FBI and Department of Energy Office of Inspector General investigation, Julianne Sohn of the FBI said in an email.

Solyndra filed for Chapter 11 bankruptcy protection this week after receiving a $535 million loan guarantee from the federal government. The company is currently seeking a buyer.