SEATTLE -- A teacher at Whitman Middle School in Seattle is under investigation and on paid administrative leave after a woman who said she dated him told police he showed her child pornography on his computer.

The woman, who said she broke up with the teacher earlier this month, said the teacher "talked ... about killing young boys" and fantasized "about having sex with underage boys," according to a search warrant obtained by KIRO 7 Eyewitness News.

According to the documents, the man told his former girlfriend that he was a "pedophile" and a "rapist."

A laptop computer, according to documents, was one of many things seized from the teacher's North Seattle home, along with external hard drives, videotapes, photos and yearbooks.

The man has taught boys and girls at Whitman Middle School in Ballard for years.

The man has not been arrested or charged.

The man could not be reached at his home on Thursday.