MONTREAL—The tiled warrens of the Ville-Marie Expressway were the scene of tragedy Saturday morning as one man was killed and four injured in what police say may have been a case of street racing.

The crashed happened around 3:30 a.m. on the eastbound Ville-Marie as both vehicles were headed towards the de la Montagne exit. The two cars collided at high-speeds below downtown.

One man was killed and two others were seriously injured in one car. Police couldn’t confirm who was driving. In a second car, one person was seriously injured and a second suffered minor injuries.

All the victims were in their 20s and knew each other.

“it’s rare we see an accident of this magnitude, where there is a death and so many injuries,” said David Sasson, a spokesman for Urgences-Sante.

Nearly 12 hours after the crash, two tow trucks pulled the mangled wrecks of both cars from the tunnel. One car was sheered in two by the impact, the second was badly damaged.

According to Sgt. Claude Denis of the Surete du Quebec, investigators were looking at the speed of the accident.

“We have to meet a witness of this collision and we also have to meet someone who was on board the other car,” said Denis.

Speeding is the leading cause of death amongst young drivers in 2011. Almost 100 drivers under the age of 24 died on Quebec roads. Despite steeper fines and a new, stricter demerit points system, getting young drivers to slow down remains a tough sell.

“We are starting to win the battle of alcohol with young drivers, but now we’ve switched to the problem of speeding,” said Jean-Marie de Koninck, an expert on driving safety who founded Operation Nez Rouge.

Having written a report on road safety for the Quebec government, de Koninck said spring inevitably brings an increase in the number of accidents like Saturday’s tragedy. Police and paramedics are urging drivers to slow down.

“When there is speeding involved with young drivers, it is very excessive speeding,” continued de Koninck. “When you combine speeding with the new phenomenon of texting, you have a plague for driving.”

Highway traffic was routed off the important thoroughfare through Saturday morning due to the ongoing investigation. Traffic continued to be detoured at Atwater Ave. until 2 p.m. causing congestion and long delays.