An exterminator discovered possible human remains inside a chimney at a Queens public school Tuesday morning, police said.

The discovery came after a school custodian noticed a foul odor and called the exterminator, suspecting rodents, according to police.

Officers responded to a 911 call at about 9 a.m. near 87th Street and 78th Avenue in Glendale, where they were told possible human remains had been found in a chimney at P.S. 113, police said.

No students or staff were in the building because it is closed for summer construction.

The city medical examiner's office will determine the cause of death, police said.

Authorities have not determined the person's age, sex or identity, how long the remains had been inside the chimney or where in the structure they were found.

The city Department of Education said in a statement that the discovery was "deeply upsetting and concerning" and that it was making sure the appropriate supports were in place for the school community while the NYPD investigates.