Calgary police have laid charges in connection with a fight near Western Canada High School last week that sent a teenager to hospital with serious injuries.

The boy was hurt when the altercation happened on Oct. 5 off school property behind a restaurant on 17th Avenue S.W.

He has since been upgraded to stable condition. A second male student was treated at the scene.

Two youths have already been charged and charges are pending against a third for assault causing bodily harm, police say.

"There is no evidence to suggest this is related to gang violence, and it is believed to only involve students from that school," police said in an email Tuesday.

One student who saw the altercation said there was a crowd of more than 100 youths, and some were fighting.

The fight is still under investigation.

The names of those charged can not be released under the provisions of the Youth Criminal Justice Act.