by Jim Kouri - LANCASTER, PA -- In what appears to be turning into a common occurrence, a gunman killed at least six people and injured several others after he walked into a small Amish schoolhouse in idyllic Lancaster County, PA and opened fire on the helpless occupants.

According to the Pennsylvania State police, the shooting spree ended with gunman turned his gun on himself. Police investigators say it's still unclear as to the shooter's motive.

The man ordered some students to leave before opening fire on the remaining students, state police spokesman Jack Lewis told the CNN, adding that at least three students were killed.

However, a medical examiner told AP that as many as 6 people have been killed during shooting melee and a number of other children have been seriously wounded from the gunfire and the ensuing panic.

"So far six confirmed dead and the helicopters are pulling into (Lancaster General Hospital) like crazy," Lancaster County's Dr. G. Gary Kirchner told the AP.

A spokeswoman for Lancaster General Hospital confirmed that the facility had received three young patients, ages 6 to 15, with one in critical condition. She told reporters that three more patients were soon expected to be admitted.

Police had surrounded the one-room school late Monday morning and cordoned off the area after arriving on the scene. Shortly after the attack, several people in traditional Amish clothing, stood near the small school building speaking to one another, several young people and authorities.

As part of their religious beliefs, members of the Amish sect are forbidden from using physical force on another human being even in self-defense.

This latest attack comes just five days after a 53-year-old man entered a high school in Bailey, Colorado, where he held several female students hostage at gunpoint and killed himself but not before shooting and killing one girl as a SWAT team stormed inside the classroom.