LONDON — At least one person was killed and 32 injured in the crash of a police helicopter onto the roof of a pub filled with revelers, with the death toll expected to rise, Scottish officials said Saturday.

[Updated 8:30 a.m. PDT Nov. 30: Scottish police have confirmed that at least eight people were killed in the crash, including all three on board the helicopter. Another 14 people remain hospitalized with serious injuries.]

An overnight search stretched into the Saturday morning for anyone still trapped in the wreckage of the Clutha Vaults bar, on the banks of the Clyde River in Glasgow. One of the yellow-tipped rotor blades of the chopper, which went down about 10:25 p.m. Friday, could still be seen poking out from the damaged building before police covered the site with blue tarpaulins.

“A full and thorough investigation into what happened last night has already begun,” Stephen House, chief constable of Scotland Police, told reporters Saturday.

The Eurocopter EC135 T2 helicopter was carrying two police officers and a civilian pilot when it crashed. Some witnesses reported hearing the chopper’s engines sputter and cut before it dropped, silently, onto the Clutha.

Inside were an estimated 100 pub-goers 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 to those in their section of the pub and that 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,” a patron named 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. The 32 people injured were taken to three hospitals.

“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.”

House did not say what mission the helicopter’s crew was carrying out or where they were heading. The Glasgow City Heliport lies about two miles west of the pub.

Gordon Smart, editor of the Scottish Sun, who was in a nearby parking structure, 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. “I’m absolutely amazed that anybody’s walked away from it. Whatever the helicopter pilot managed to do, he’s certainly done something amazing to save that helicopter from hitting a block of flats where people were asleep in bed.”

A few hours after the crash, firefighters said they had established contact with people trapped in the debris. But hopes of rescuing more survivors appeared to fade as a clear morning dawned in Glasgow.

House confirmed that one person had been killed, adding: “We are fearful there will be more.” Sky News, citing unidentified sources, said at least six people were dead.

“This is a dreadfully sad day in my home city,” said Gordon Matheson, leader of the Glasgow City Council. “Thankfully, these kinds of tragic incidents happen rarely. But you always imagine somehow that it’s going to be somewhere else.”

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Twitter: @HenryHChu

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