A construction worker died this morning after falling about five stories while working at a site on the Temple University Hospital campus in North Philadelphia, authorities said.

Medics were sent to the site at 3500 North Broad Street, near Venango Street, shortly after 8 a.m., said Capt. Richard Davis of the Philadelphia Fire Department.

The 44-year-old victim, whom authorities did not immediately identify, was rushed to Temple University Hospital, where he was pronounced dead at 8:15 a.m.

Investigators are trying to determine what caused the fall. Police were initially told the man fell from the 10th floor to the fourth floor, where he landed on rebar wire. Davis said he believes the victim had been on scaffolding equal to five stories.

Investigators from the Office of Safety and Health Administration were also called to the scene.

One OSHA investigator, John Quinn, said it appeared the worker - who was wearing a harness - was welding on an improvised floor structure when he fell.

Contact staff writer Barbara Boyer at 215-854-2641 or bboyer@phillynews.com.