Emergency workers tend to victims of a two-vehicle accident at the intersection of Route 136 and Brownlee Road Thursday in Somerset Township. Five people were killed and seven injured.

EIGHTY-FOUR — A tractor-trailer slammed into a van carrying mentally disabled people on a trip to the Pittsburgh Zoo, flipping it onto its side and crushing it against a building. Five people were killed and seven injured.

Witnesses told investigators the van stopped at an intersection and then pulled right in front of the tractor-trailer on a rural highway. Crews worked for several hours Thursday to remove all the bodies from the van.

The accident happened at about 9:45 a.m. in Somerset Township, about 30 miles south of Pittsburgh, just minutes after the van left a group home in Bentleyville.

"I just think it's one of those terrible, sad, freak accidents," said Lynne Loresch, executive director of the Mental Health Association of Washington County, the group home operator.

The van was carrying 11 people. Five of them were killed — three residents and two staff members. Six other residents inside were taken to area hospitals. The tractor-trailer driver also was treated and released from a hospital.

Authorities did not believe the tractor-trailer was speeding. State transportation officials hauled it from the scene and planned to inspect it. Authorities could not say what was in the tarp-covered, open-top trailer.

The tractor-trailer was owned by Stocker Trucking Co. in Gnadenhutten, Ohio, and driven by Stephen Rouse, 44, of Uhrichsville, Ohio. A man who answered the phone at Stocker Trucking declined to comment.

The van was pinned against a cinderblock storage building owned by a home gas- and oil-delivery business; a corner of the building partly collapsed.

The van was knocked onto its side and pushed roof-first into the building, causing the vehicle's roof to cave in, state police Trooper Frank Lewis said.

Two of the dead were removed by paramedics shortly after the accident, while the bodies of the driver and two residents had to be cut from the wreckage, Washington County Coroner Tim Warco said. By mid-afternoon, all five bodies were removed from the van.

Killed in the crash were: the driver, Sheryl Maiolini, 53, of Charleroi; staff member Mary Watkins, 43, of Ellsworth; and residents John Maise, 61, Richard Paquet, 43, and Julie Hugus, 41.