A gunman who killed three people and wounded 13 others in an attack on a Christmas market is wanted "dead or alive".

French security forces stepped up the manhunt for a 29-year-old suspect as a third person died after the attack in Strasbourg. 

More than 700 officers are involved in the hunt for Cherif Chekatt, who had been flagged for extremism, as prosecutors open a terror investigation into Tuesday's attack.

The Herald:

An image of Chekatt, who was wounded in a stand-off with security forces, was released with the warning: "Individual dangerous, above all do not intervene."

The government raised the terror alert level nationwide and deployed 1,800 additional soldiers across France to help patrol streets and secure crowded events.

The Herald:

Mr Griveaux also called on the "yellow vest" protesters not to take to the streets, as some members of the movement have planned a fifth round of demonstrations on Saturday across France to demand tax relief.

Meanwhile Strasbourg mourns, with candles lit and flowers left at the site of the attack.

Read more: French police use armoured vans and tear gas in bid to quell Paris protests

The Christmas market was closed where the attack took place remains closed today.

On Wednesday evening, people prayed and sang in the nearby Protestant Church Saint-Pierre-le-Jeune.

Pastor Philippe Eber said this is a moment "to think of those who died in this city because of violence. We also are thinking about all of those who weep for them, the families".

The Herald:

Strasbourg resident Tassia Konstantinidis said "it's important to have a period of mourning and to remember the victims".

The dead included Thai tourist Anupong Suebsamarn, who was 45.

Italian Interior Minister Matteo Salvini said one Italian was among the wounded, in critical condition. The Europhonica radio consortium said Antonio Megalizzi, 28, was in Strasbourg to follow the session of the European Parliament when he was shot.

French authorities said that the suspect, born in Strasbourg, had run-ins with police from the age of 10 and his first conviction was at 13.

Chekatt had been convicted 27 times, mostly in France but also in Switzerland and Germany, for crimes including armed robbery. He had been flagged for extremism and was on a watch list.