Strasbourg  - Police and around 150 anti-NATO campaigners clashed overnight on the outskirts of the French city of Strasbourg after police initiated identification checks in the run-up to the upcoming NATO summit, protesters reported Wednesday.

Police were said to have used tear gas and other anti-riot devices against the group who had gathered to protest stricter controls of identification. The situation was returned to calm around 1100 pm (2100 GMT) Tuesday night.

The city prefecture could not confirm the incident.

The anti-NATO activists claim that a number of their members were prohibited from entering France and have called for a protest action in the German city of Kehl in solidarity with those arrested and turned back.

The first demonstrations are planned for Wednesday. The summit of the North Atlantic Treaty Organization is to take place on Friday and Saturday both in Strasbourg and Kehl. (dpa)