Two people suffered life-threatening injuries in a head-on collision in Topsham on Thursday.

A 1995 Saturn driven by Ashlee Cleveland, 23, of Durham was headed west on Route 196 near Old Lisbon Road when the car crossed the center line, police said. The car collided with an oncoming 2004 Suzuki Vitara driven by Lori Gates, 51, of Lisbon.

Topsham firefighters and a LifeFlight of Maine helicopter responded. Both drivers were extricated from their cars and taken to Central Maine Medical Center in Lewiston, Cleveland by helicopter and Gates by ambulance, authorities said.

Cleveland was in critical condition Thursday afternoon, according to a hospital spokeswoman. Gates was in serious condition, police said Thursday night.

Route 196 was closed or had restricted traffic flow for four hours as Topsham and Bath police and a Maine State Police trooper investigated the collision.

It could take several days to determine what caused the crash, Topsham Police Chief Christopher Lewis said.

Cleveland has no speeding tickets or other moving violations on her driving record, but has had three crashes, according to state records.

On Jan. 7, 2013, Cleveland was driving on Court Street in Auburn when she ran a red light and collided with another car.

On Jan. 30, 2013, she was driving too fast for icy conditions and lost control of her car, hitting a utility pole.

In 2009, on a rainy afternoon in Durham, she veered off Route 136 and into a tree, according to a crash report. She told police she looked down for an unknown reason and ran off the road.

Nobody was injured in any of the crashes.