WASHINGTON — The government is still searching for evidence that Bruce Ivins was solely responsible for the 2001 anthrax attacks despite declaring the case solved.

Search warrants and other documents filed Thursday in federal court in Washington show the FBI wants to look through computers Ivins used at his local library before he killed himself last week.

Agents are looking for anything he may have written about plans to kill or hurt people, a suicide note or other data linking him to the 2001 attacks that killed five people.

Ivins was under FBI surveillance when he was seen using two computers at the library not far from his home in Frederick, Md. FBI agents said they watched him read e-mail and a Web site about the anthrax attacks.