Four men are facing charges of attempted murder and aggravated assault after a 21-year-old man was found naked and "severely beaten" in an Ottawa park on Sunday morning.

A passerby found the unconscious man near a parking lot in Andrew Haydon Park in the city's west end around 9:30 a.m. Sunday. 

Police said he was naked and suffering from serious injuries after being "severely beaten."

Four men, each known to the guns and gangs unit, were arrested. They are each facing a charge of attempted murder and a charge of aggravated assault. One of the men was also charged with failing to comply, police said.

More charges could be laid as the investigation continues.

The names of the charged men are not being released due to a publication ban. 

Anyone with information is asked to call the west district investigations unit at 613-236-1222, ext. 2666, or Crime Stoppers at 613-233-8477.