Washington, Sep 14 (DPA) At least 20 people were injured after a gunman opened fire inside the cafeteria of a Montreal college.

Eight of the injured are reported to be in critical condition.

Police said one gunman was killed, whom they now believe acted alone. Canadian television had earlier reported that up to four gunmen fired shots inside Dawson College in downtown Montreal Wednesday.

Students told CTV broadcaster they heard about 20 shots fired on the campus. Witnesses said that the shooting lasted for about 30 minutes.

Television footage showed terrified students fleeing the college building.

In 1989 a gunman shot 27 women engineering students and killed 14 in Montreal, prompting Canada to severely tighten its gun laws.