French police have used tear gas to stop hundreds of protesters from disrupting Nato's summit in Strasbourg.
Demonstrators threw stones and petrol bombs, causing fires near the summit venue.
On the French side of the River Rhine, demonstrators set alight a hotel and a customs house.
Three columns of smoke could be seen rising over the Europe Bridge area in Strasbourg, across from the small town of Kehl in Germany, where part of the summit was held.
While some protesters sauntered nonchalantly, 25 people were arrested, adding to dozens detained in the run-up to the gathering.