A gunman is reportedly on the run in Strasbourg, France after shooting two people dead and injuring at least 11 others in a terrorist attack near the city’s celebrated Christmas market, on Tuesday evening.

Police said the lone gunman started his attack in the city centre just before 8pm where the market, which attracts millions of tourists every year, is taking place.

The motive behind the attack was not immediately clear but, with France still on high alert after a wave of attacks commissioned or inspired by Islamic State militants since early 2015, the counter-terrorism prosecutor opened an investigation.

Several of the injured are reported to be in a critical condition.

A restaurant waiter told BFMTV how staff and customers tried to save a diner who stepped outside and was shot. “We used napkins to try to stem the blood.” He said the man had died.

People in the city’s Neudorf area and Etoile park were told to stay where they were as officers hunted the shooter on the ground and from the air.

The European Parliament, which is sitting in Strasbourg this week, was put into lockdown.

In 2016, a truck ploughed into a Bastille Day crowd in Nice, killing more than 80 people, while in November 2015, coordinated Islamist militant attacks on the Bataclan concert hall and other sites in Paris claimed about 130 lives. There have also been attacks in Paris on a policeman on the Champs-Elysees avenue, the satirical weekly Charlie Hebdo and a kosher store.

Almost exactly two years ago, a Tunisian Islamist rammed a hijacked truck into a Christmas market in central Berlin, killing 11 people as well as the driver.