A teenage boy has been rushed to hospital with serious injuries after being stabbed at a plaza near an all-boys Catholic high school in the area of The Beaches.

Toronto police said in a tweet that the victim was found inside Neil McNeil High School at Victoria Park and Bracken avenues.

However the Toronto Catholic District School Board later said that the stabbing did not occur on school property.

"This afternoon during the lunch hour, while some of our students were off school premises one of our students was accosted by unknown males, and one student was stabbed in the altercation," TCDSB spokesperson Fiona Persaud said in an email.

He was transported to hospital in serious, but stable condition, Toronto Paramedic Services said.

The school was placed under a hold-and-secure order as a precaution, but the order has since been lifted.

The school board said that supports will be put in place for students as needed following the incident.

There is no suspect information so far.