A teenager is fighting for his life after a suspected school stabbing.

The 17-year-old boy suffered life-threatening injuries after an altercation at the Islamic College of Brisbane on Tuesday.

The incident occurred between two teenage boys known to each other at the school in Brisbane’s south about 11.45am, police said.

“A 16-year-old boy is assisting police with inquiries,” a police statement said.

Patrols were being conducted in the Karawatha area surrounding the school on Tuesday afternoon as police appealed for information.

The college confirmed the incident in a post on Facebook.

“Following a serious incident this morning, the college immediately contacted the Queensland Police Service and Queensland Ambulance Service,” it said.

“At the same time, our school went into a short lockdown under established procedures to ensure the safety of all students and staff while we waited for emergency service to arrive.”

It said students and staff had been sent home after the incident.

It is the second stabbing at a Queensland school in as many days.

A 15-year-old boy was taken to hospital in a stable condition following an altercation at a high school in the state’s far north about 11.40am on Monday, police said.

He sustained wounds to the abdomen at Cairns’ Trinity Bay State High.

A second 15-year-old boy fled on foot and was found nearby about half an hour later, police said.

He was charged with acts intended to cause grievous bodily harm, refused bail and set to appear in Cairns Children’s Court on Tuesday.

-with AAP