Protests and strikes against unpopular pension reforms kicked off again Tuesday across France, with police security ramped up against feared violence and government warnings that radical demonstrators intend “to destroy, to injure and to kill.” Fears that violence could mar the demonstrations prompted what Interior Minister Gérald Darmanin described as an unprecedented deployment of 13,000 officers, nearly half of them concentrated in the French capital.

The protests got underway peacefully Tuesday morning across the country. In Paris, striking railway workers with burning flares and flags invaded and blocked train tracks at Gare de Lyon. But police braced for violence later in the day. The interior minister said more than 1,000 “radical” troublemakers, some from overseas, could latch on to marches planned in Paris and elsewhere.