A Washington state prison escapee who was serving five consecutive life sentences for aggravated rape may be in the San Diego area, an FBI spokesman said. David Sterling, 40, is considered extremely dangerous and might kill if it meant avoiding a return to confinement, said Gary Laturno, an FBI spokesman. Sterling was convicted of the aggravated rapes in Clark County, Wash., in 1982 and was sentenced to five consecutive life sentences. The escapee was transferred to Washington State Hospital for treatment as a sexual psychopath and escaped Feb. 28, he said. Sterling was last seen March 1 in San Francisco, where he withdrew $15,000 from his bank account and cashed cashier's checks worth an additional $15,000 in a Bank of America branch, Laturno said. He apparently told the bank tellers he was headed for San Diego. He is described as 5-foot-10, with brown eyes and black hair.