For the second time in three weeks, families in the Upper Pottsgrove area of Montgomery County are reeling from the deaths of two high school students in a nighttime crash of an SUV crowded with teenagers.

This time, the victims were ninth-grade girls.

They were killed in a single-vehicle crash late Saturday night in Upper Pottsgrove Township, the Montgomery County District Attorney's Office said. The crash happened about 11:50 p.m. on Route 100 near Moyer Road.

An SUV carrying six people was traveling north when it went off the road, struck a guardrail, and flipped over. The two girls, in rear seats, were ejected from the vehicle, authorities said. The conditions of the other passengers were not disclosed.

The crash was under investigation yesterday, First Assistant District Attorney Kevin Steele said. He declined to identify the victims.

Both girls were students at Pottstown High School, said John Armato, director of community relations for the Pottstown School District. He said school officials were setting in motion grief counseling and other outreach to pupils and families.

The crash was similar to one on Nov. 23 in which two Pottsgrove High School students were killed. The Honda SUV in which they were riding went out of control and crashed into a car on Route 724 in East Coventry Township, Chester County.

Contact staff writer Carolyn Davis at 215-854-4214 or cdavis@phillynews.com.