NEW YORK -- Police are investigating after officers found an 80-year-old man shot dead in the Bronx. 

Officers were on patrol in the Highbridge section when they heard gunshots shortly after 1 a.m. Sunday and found the man with a gunshot wound to the head. 

The man, identified as Marcelino Valerio of Mount Eden, was pronounced dead at the hospital. 

Surveillance video shows the victim walking to the door of a building. Seconds later, a suspect on a bike approaches the man and fires from just feet away.

No arrests have been made.

Anyone with any information is asked to call the NYPD's Crime Stoppers hotline at 1-800-577-TIPS (8477), or for Spanish, 1-888-57-PISTA (74782). You can also submit a tip via their website or via DM on Twitter, @NYPDTips. All calls are kept confidential.