An offer to sell marijuana set off a scary chain of events at an Oshawa high school.

Durham police say around 1 p.m. Tuesday, several teenage students of the Durham Alternative Secondary School were outside the school hanging out when a car pulled up.

Two men were inside and one asked the group if they wanted to buy some weed.

The students said no and an argument started.

One of the men got out of the car, threatened them and flashed a gun which was tucked into his waistband.

Several students then followed the car to a roundabout near the school.

Police say one of the men got out of the car and pointed the gun at a student and spit in the face of another.

The car took off, heading northbound on Simcoe Street.

No students were physically hurt.

Both suspects are described as black, with light complexions.

One may have had a tattoo on his neck.

The vehicle is described as a light blue 2005/6 Volkswagen Jetta.

Anyone who can help identify them is asked to call police at 1-888-579-1520 ext. 1747 or Crime Stoppers at 1-800-222-8477 (TIPS).