Police are investigating the allegations of assault and theft filed by the photographer against Ruffalo after the Saturday incident, TMZ.com reported Monday.
Ruffalo allegedly took the photographer's video card from his camera during the altercation at the private funeral for Penn's brother Saturday.
A police source told TMZ.com the department has taken into account that Holy Cross Cemetery is private property and the photographer did not have permission to be there, but confirmed it is investigating the charges against the star of "Rumor Has It."
Chris Penn, 40, was found dead in his apartment last week. A cause of death has not yet been determined.