FBI divers have wrapped up a three-day search of a lakebed where authorities suspect a couple inspired by Islamic State dumped evidence linked to their massacre of 14 people, an official said on Sunday, adding that the team retrieved some objects there.

Laura Eimiller, a Federal Bureau of Investigation spokeswoman, declined to describe the objects or say whether they appeared to be connected to the mass shooting earlier this month.

"We have not commented on the items, or whether they are case-related, due to the ongoing investigation," Eimiller said, responding to a media report that the objects were not tied the crimes under investigation.