NICKEL MINES, Pa. (AP) - A gunman killed “a number” of people at a one-room Amish schoolhouse today in Pennsylvania's Lancaster County, state police said.

The shooter was among the dead, state police Cpl. Ralph Striebig said.

“There are a number of people dead,” Striebig said. “The exact number I do not know yet.”

The person who fired the shots was among those killed, Striebig said. There are also a number of casualties, he said.

Police surrounded the one-room school in southeastern Lancaster County late thismorning. The Lancaster County 911 Web site reported that dozens of emergency units were dispatched to a “medical emergency” at 10:45 a.m. today.

Officials at the Penn State Milton S. Hershey Medical Center confirmed that victims were being admitted there. A spokeswoman said the hospital anticipated treating more than one patient, but did not know how many.

About three dozen Amish people were seen standing behind a police line, and at least two ambulances had left the scene. Television news helicopters also showed a person being taken away on a stretcher to a waiting medical helicopter.