LONDON — Authorities began combing through the wreckage of a Scottish pub Saturday for clues as to why a police helicopter plunged onto its roof, killing at least eight people, including all three on board, and seriously injuring 14.
"A full and thorough investigation into what happened last night has already begun," Stephen House, chief constable of Scotland Police, told reporters in the city of Glasgow, which awoke to an extraordinary scene of damage on the banks of the River Clyde.
House confirmed that two police officers aboard the helicopter and the civilian pilot died, as well as five people inside the Clutha Vaults bar on Stockwell Street. Thirty-two people were taken to hospitals, 14 of them with serious injuries.
Rescue crews searched for anyone still trapped in the rubble of the pub, though hope of finding survivors faded as the hours passed. Earlier Saturday, as a clear day dawned, one of the yellow-tipped rotor blades of the downed chopper could be seen poking out from the tavern's roof before police covered the site with blue tarpaulins.
Workers attempted to stabilize the building, and a massive crane towered over the damaged structure Saturday evening. On the ground, well-wishers laid flowers in tribute to those who died.
The Eurocopter EC135 T2 helicopter fell out of the sky about 10:25 p.m. Friday. Some witnesses reported hearing the chopper's engines sputter and cut before it plummeted, in a silent free fall, onto the Clutha.
Inside were an estimated 100 people enjoying live music and celebrating on the eve of St. Andrew's Day, Scotland's national day. Several witnesses said the disaster was not apparent at first, at least in their section of the pub, and the ceiling did not immediately collapse.
"No one had a clue what was going on. There was no loud noise. ... No one knew a helicopter crashed till people told you," patron Grace MacLean told Sky News. "There was just a gradual coming down of the roof and some dust. It wasn't like an instantaneous bang and explosion."
Customers — some coughing, others bleeding — led one another through the rubble to the exits, witnesses said. Bystanders, including a member of the British Parliament, rushed to help those struggling to get out.
"This is a black day for Glasgow and for Scotland," First Minister Alex Salmond said. "But it's also St. Andrew's Day, and it's a day we can take pride and courage in how we respond to adversity and tragedy."
British Prime Minister David Cameron issued a statement of condolence. "This is a tragic event, and our deepest sympathies are with the families and friends who lost a loved one last night," Cameron said.
At soccer matches throughout Scotland, teams paused for a minute of silence. Flags were to fly at half staff through the weekend.
House did not say what the helicopter crew's mission was or where they were heading. The Glasgow City Heliport lies about two miles west of the pub.
"Three of these eight fatalities were found in the helicopter and were our colleagues," House told reporters, visibly struggling with emotion.
Gordon Smart, editor of the Scottish Sun tabloid newspaper, was in a nearby parking structure and said he saw the helicopter "tumbling nose over tail at a huge pace" before it vanished behind the buildings in front of him.
"Just to see the trajectory and speed of the helicopter's descent, it really was dramatic and terrifying," he told the BBC.
A few hours after the crash, firefighters said they had established contact with victims trapped in the debris. But House could not say whether those people were rescued.
"We are dealing with a very sensitive investigation and operation here," House said. "It will go on for many days yet."
Gordon Matheson, leader of the Glasgow City Council, said it was a "dreadfully sad day" for Scotland's most populous city.
"Thankfully, these kinds of tragic incidents happen rarely. But you always imagine somehow that it's going to be somewhere else."