Traffic was at a standstill on the north perimeter following a rollover Tuesday morning. 

The collision happened on Highway 101 near Highway 6 shortly after 8 a.m. with a single-vehicle rollover.

STARS air ambulance was dispatched to the scene. They transported a 25-year-old male in serious but stable condition out of the area.

The cause of the crash remains under investigation.

More to come.