HALIFAX -- Halifax Regional Police say a woman has died after the vehicle she was driving collided head-on with a city transit bus.

Police say the three-vehicle collision happened on Old Sambro Road near the Halifax community of Harrietsfield shortly after 5 p.m. on Friday.

Officers say a third vehicle rear-ended the woman's vehicle after the initial crash.

The 45-year-old woman had to be extracted from her vehicle and was taken to hospital with serious injuries, where she later died.

Her name is not being released pending the notification of family.

There were five people on the bus at the time of the crash, but no one was injured.

The only occupant of the third vehicle was also unharmed.

The road was shut down for more than four hours as police investigated.