One firefighter was killed and three others were feared dead after a warehouse roof collapsed as they battled a suspicious blaze in central England, police and fire chiefs said.
Union leaders said that if the missing firefighters were confirmed dead it would be the fire service's worst loss of life in decades.
More than 80 firefighters were called to the blaze yeserday evening at a vegetable packing warehouse on an industrial estate near Stratford upon Avon, Warwickshire.
Fire crews worked through the night to bring the blaze under control. At its peak, the flames could be seen for miles around. Aerial television pictures showed plumes of smoke and steam still rising from the charred warehouse this morning. Large sections of the roof collapsed into the single-storey building.
"Three of our firefighters are still missing and we have grave concerns for them," Warwickshire County Council's Chief Fire Officer William Brown told a news conference.
Police are treating the fire as suspicious. The cause of the blaze is not yet known.
"A major police operation into last night's fire has begun," said Assistant Chief Constable Bill Holland. "The fire is being treated as suspicious and this will remain the case until we have established the cause."
West Midlands Ambulance Service Chief Executive Anthony Marsh said it was "one of the darkest days in the history of emergency services in Warwickshire".
Fire Brigades Union General Secretary Matt Wrack said the service was traumatised. "This is the worst loss the fire service has faced in decades," he said.