Three people are seriously injured in a head-on collision in West Penn Township.

It happened Tuesday night around 10:00 on Route 309.

A woman was heading south when for an unknown reason she crossed over three lanes of 309 and into a tractor trailer coming the other way.

She and the two children in her car were all seriously injured. Two of them had to be flown by MedEvac.

The driver of the tractor trailer was not injured. West Penn Township police are investigating that crash.