Police in northern Illinois are investigating the apparent shooting deaths of a man and his two young sons as a triple homicide and are searching for the man's missing vehicle. 

Officers found the bodies of Andrew Hintt, 31, and his two sons, 5 and 7, at their home in Belvidere on Sunday night, police said Monday. Autopsies are pending. 

Four shell casings were found at the scene, but no weapons have been recovered, police said. 

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Police are searching for Andrew Hintt's 2018 Jeep Grand Cherokee Trailhawk.

Police are searching for Andrew Hintt's 2018 Jeep Grand Cherokee Trailhawk. (Artur Widak/NurPhoto via Getty Images)

The bodies were found after the boys' mother contacted the landlord to say she had not heard from anyone in the family. The landlord called 911 and officers responded, police said. 

Belvidere Police Chief Shane Woody said the deaths are being investigated as a triple homicide. 

"Whoever did this horrific act is truly evil," he said Monday during a news conference. Belvidere is about 70 miles northwest of Chicago. 

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Officers are searching for Hintt’s vehicle, a silver or gray 2018 Jeep Grand Cherokee Trailhawk with Illinois registration: CT92923. 

Police asked anyone who knows anything about the vehicle's whereabouts or anything else regarding the case to contact the Belvidere Police Department at 815-544-2135 or Boone County Crime Stoppers at 815-547-7867.