An animal rights activist sought in the bombings of two California drug and cosmetic companies may be living in Costa Rica, the FBI said Tuesday.

Daniel Andreas San Diego, 30, of Berkeley, Calif., could be living and working with Americans or people who speak English in the Central American country, the FBI said in a statement released to Costa Rican media by the U.S. Embassy.

"He has links with animal rights groups in the U.S., and he could be linked with similar organizations in Costa Rica," the FBI said. A $250,000 reward is offered for information leading to his arrest.

San Diego is wanted in connection with the 2003 bombings in northern California of the corporate offices of Chiron Corp., an Emeryville biotechnology firm, and at Shaklee, a Pleasanton cosmetic company. The explosions caused minor damages and no injuries.

A group calling itself "Revolutionary Cells" took responsibility for the blasts, telling followers in a series of e-mails that the firms had been targeted for their ties to a research company that conducted drug and chemical experiments on animals.