The remains of 11 babies were discovered Friday above the ceiling of a shuttered funeral home in Detroit, police said.

Officials with a state regulatory agency found the tiny bodies in a cardboard box and casket hidden above a first-floor ceiling at the Cantrell Funeral Home after receiving an anonymous letter that contained the exact location of the remains.

"They're very small remains, OK," Detroit police Lt. Brian Bowser said at a Friday night news conference.

He said police were working with the medical examiner's office to identify the bodies and notify family members.

Jason Moon, a spokesman for the Michigan Department of Licensing and Regulatory Affairs, described the remains in a statement as "decomposing bodies."

The funeral home has been closed for about six months because of alleged workplace violations and an ongoing state investigation.

"We will use the evidence gathered today to add to our open investigation and will continue to work with local law enforcement as this case proceeds," Moon said.

A cadaver dog later went through the two-story building but did not find any other bodies, he said.

Bowser criticized "the callousness of ... the owners and the employees of the funeral home."

He said police want to interview former owner Raymond Cantrell, who spoke to NBC News affiliate WDIV in Detroit Friday night.

"On behalf of my family, I'm really sorry that it happened and totally appalled," Cantrell said. "The fact it occurred. I'm just thanking God it wasn't something I had any involvement in."

The state licensing agency announced in April that the funeral home had been shut down because of multiple occupational code violations and "an imminent threat to the public health and safety."

The allegations included "improper storage of embalmed bodies" and "an unclean and unsanitary embalming room, with peeling and chipping paint, water stained walls, dirty floors, and stained protective gear," department officials said in a statement.

The statement did not name Raymond Cantrell. The funeral home's mortuary science license was suspended, as was the license of "designated manager" Jameca LaJoyce Boone.