Detectives hauled out more children’s clothes from murder suspect Levi Aron’s apartment yesterday and are investigating whether he is a first-time killer, law-enforcement sources told The Post.

The theory is based on 35-year-old Aron’s age and the manner in which 8-year-old Leiby Kletzky was murdered, the sources said.

Cops took bags marked “kids pants” and “blue child’s spoon, pink cup” from the attic apartment and will run the items through the DNA database to see if they match other cases, sources said.

The loser loner stashed the items in the East Second Street home in Kensington, Brooklyn.

“There were two boxes in a closet, and they appear to have been there for a while,” said a source.

They also carried out bags of shirts and jackets and 12 filing boxes.

READ MORE: NY POST