Philadelphia police were investigating the stabbing death of an 80-year-old man inside his Port Richmond home.

The body of Robert Girard was discovered by his granddaughter around 9 p.m. Wednesday, said Homicide Capt John Ryan. She found his naked body in the kitchen and there was a blood trail leading to the man's second-floor bedroom.

Ryan said there were no signs of forced entry and nothing appeared to have been taken.

Police towed away a white commercial van that had been parked in front of the man's home on the 2500 block of East Lehigh Avenue. Neighbors told 6ABC a man had been living in the van for about a month and the victim's grandson told the station his grandfather had argued with the man.

Relatives said Girard was an army veteran, 6ABC said.