A 41-year-old mother and community activist from Richmond Hill has died and three others were injured after a collision on Highway 401 near Belleville on Sunday.

Taline Yacoubian was on her way to Kingston when her car -- a 2008 Buick Enclave -- veered off the eastbound lanes of the highway and struck a tree, just east of Highway 37.

She was pronounced dead at the scene.

Her 16-year-old son was in the car along with a 25-year-old woman from Toronto and a 47-year-old man from Markham, according to the Ontario Provincial Police. All three were injured in the crash.

The older man was airlifted to Kingston General Hospital for emergency treatment. The two others were treated at the Quinte West Medical Centre. The young woman has since been released.

Yacoubian's son remains in hospital with broken legs.

Police say the group was on their way to a youth leadership conference in Kingston.

Yacoubian was a youth leader and was heavily involved with Toronto's Armenian community, according to a friend of the family who didn't want her name published.

Yacoubian leaves behind three children, the youngest of whom is about 10 years old. Her husband, who owns a hair salon in east-end Toronto, is also well-known in the community.

"Taline always encouraged her sons to be part of the community, they were in all the plays," the friend told ctvtoronto.ca in a telephone interview. "She always volunteered her time and was always committed."

OPP say they are still trying to determine what caused the crash.

An autopsy on Yaacobian's body was scheduled for Monday.