A teen bystander was shot during an altercation outside the Edmonton Convention Centre Thursday evening, police say.

Two groups were involved in the dispute around 11 p.m. Investigators did not say what caused the argument but believe the people in the groups knew each other.

During the altercation, several shots were allegedly fired by a male from one of the groups, Edmonton Police Service said.

One of those shots struck a 17-year-old female bystander, who was not part of the altercation.

Another member of the public drove her to hospital. She was expected to survive, EPS said on Friday.

Two males were taken into custody. Police did not reveal their names or ages or say whether charges were pending.

The shooting happened after the Grade 12 commencement ceremony for Archbishop OLeary High School at the conference centre, according to a letter sent home to parents from school principal Brad Koshka.

Koshka did not disclose whether the victim or suspects were members of the school community.

The letter said the planned Grade 12 graduation event at the conference centre for Friday night would go ahead as planned with additional security precautions, but would now end at 10 p.m.

EPS will be deploying additional officers to the venue and area, Koshka wrote. The Edmonton Convention Centre will be heightening its security with bag checks and metal detectors for all guests entering the venue.

The school is offering refunds to anyone who chooses not to attend as a result of the events of Thursday night.

Koshka said the Edmonton Catholic Schools Crisis Response Team is available to anyone who may have seen or heard anything after Thursdays event. 

A spokesperson for the Edmonton Catholic School Board told CTV News Edmonton the commencement ceremony had ended about an hour before the incident, and said the victim is not believed to be an Archbishop OLeary student.

Anyone with information or video of the shooting is asked to contact police or Crime Stoppers.