LOCKPORT, IL — Autopsies are now scheduled for Wednesday for a man and woman found dead inside a vehicle in the parking lot of the Lockport Walmart store, 16241 S. Farrell Road.

Lockport Deputy Chief Ron Huff said the man, 53, and woman, 37 "appeared to have been sleeping in the vehicle before their deaths, so we are investing the possibility of this being carbon monoxide poisoning, but are not ruling out a drug overdose."

There was no sign of violence, Huff said, adding, "we will know more about the cause of death once an autopsy is performed."

The names of the man and women are being withheld pending notification of family, police said.

Police responded to a report of two unresponsive people in a vehicle around 5:45 p.m. Monday.