Riot police on guard behind a fire yesterday as refinery workers staged a blockade of the oil depot of Douchy-Les-Mines in northern France, to protest against the government's proposed labour reforms. Refinery workers stepped up strikes that threatened to paralyse France weeks ahead of the Euro 2016 football tournament, as the government moved to break their blockades, escalating a three-month tug-of-war over labour reforms. Faced with shortages at dozens of petrol stations, France has mobilised its strategic oil stocks for the first time since the last major refinery strike in 2010, but officials said there was no underlying shortage, and no risk of one.