REUTERS/Russell Cheyne
Witnesses said the helicopter dropped from the sky like a stone onto the busy Clutha Pub in Scotland's biggest city on Friday night while more than 100 people were crammed inside, listening to a live music concert.
The helicopter crew - two police officers and the civilian pilot - were among the dead and the others were discovered inside the wreckage of the building, Chief Constable of Police Scotland Stephen House told reporters. He said 14 others remained in hospital with serious injuries.
The 12-metre (40 foot) helicopter - a twin-engine Eurocopter EC135 T2, made by a subsidiary of EADS - spiraled into the pub in the center of Glasgow, destroying part of the roof.
The mangled wreckage remained embedded in the middle of the building as the search continued through Saturday.
"We are still in ... a rescue and recovery situation," House said. "Until the helicopter is out of the way we won't know what ... is going on underneath."
Immediately after the crash, revelers caked in dust and blood rushed out into the street. Passers-by including the local member of parliament formed a human chain to bring out the injured from the building.
"It was fairly busy, we were all having a nice time and then there was like a 'whoosh' noise," Grace MacLean, who was in the pub at the time, told the BBC.
"There was no bang, no explosion, and then there was what seemed like smoke, and we were all joking that the band had made the roof come down, and then it started to come down more and someone started screaming, and the whole pub filled with dust and you couldn't see anything, you couldn't breathe."
"BLACK DAY FOR SCOTLAND"
Tearful relatives and friends of those caught up in the incident gathered during the day, some laying flowers at the scene, and Queen Elizabeth and Prime Minister David Cameron were among those to express their sympathy.
"This is a black day for Glasgow and for Scotland," said Scottish First Minister Alex Salmond, noting that Saturday was St Andrew's Day, Scotland's national day.
Celebrations in Glasgow were canceled, flags were flown at half-mast on government buildings and a special service was held at Glasgow's Roman Catholic cathedral.
Police said it was too early to speculate on what caused the Eurocopter, popular with emergency services worldwide, to come down. Witnesses said it did not appear to have caught fire.
The Air Accident Investigation Branch began an inquiry and Eurocopter said its experts were on standby to help.
The British Airline Pilots' Association (BALPA) said safety issues had to be examined after a number of fatal helicopter crashes in recent years.
In August, four people were killed when a Super Puma L2, also made by Eurocopter, crashed into the sea off Scotland's Shetland Islands with oil workers on board, the fifth accident in four years in the area involving different models of the aircraft. Investigators said there was no evidence of technical failure.
"Whilst there will be understandable questions on why this happened, it is our experience that speculation about causes is often wide of the mark," BALPA said in a statement.
"Nevertheless, trends in helicopter safety (are) a matter of concern after a number of recent incidents."
(Writing by Michael Holden and Guy Faulconbridge; Editing by Kevin Liffey)