Six people have died after an out-of-control bin lorry careered through streets packed with Christmas shoppers, knocking down pedestrians "like pinballs".

Witnesses described bodies lying in the road after the accident which happened as the city centre was crowded with Christmas shoppers.

Police Scotland declared a major incident and confirmed six people had died in a brief statement issued shortly before 6pm.

An earlier statement said: "A Glasgow City Council bin lorry was travelling north on Queen Street when it appeared to strike pedestrians outside the Gallery of Modern Art (Goma) before continuing to travel towards George Square, when it crashed at the Millennium Hotel on Queen Street at George Square."

Eight people were seriously injured and taken to three hospitals, including the Southern General, the Western Infirmary and Glasgow Royal Infirmary.

Roads surrounding George Square were closed as emergency vehicles dealt with the aftermath.

By Monday night, police erected a steel cordon around the scene.

First Minister Nicola Sturgeon said flags on Scottish Government buildings would fly at half mast, and plans were under way for a special church memorial service. The Christmas lights in George Square were also switched off as a mark of respect.

Restaurant owner George Smith told the BBC he heard that the bin lorry driver had suffered a heart attack and the vehicle careered along the street before hitting the pedestrians outside the Millennium Hotel.

He said the emergency services were on the scene within minutes, adding: "It's really, really sad."

John Maclennan said: "Bin lorry ran all the way up Queen Street into George Square, awful."

Witness Melanie Greg told Sky News the lorry travelled 150 yards along the pavement until it crashed into a building.

She said: "The bin lorry just lost control. It went along the pavement, knocking everyone like pinballs.

"There was a baby in a buggy, and it just continued knocking people down until it ended up in the building. Quite horrific, very scary.

"The only way it stopped was hitting the building.

"People were trying to run out of the way. But when something was coming out behind them like that, how can they run out of the way? It was such a horrific thing. Just horrible. You don't expect something to be coming along behind you like that to knock you over.

"There was noise, bangs, screams and everything. It was just horrific."

Superintendent Stewart Carle of Police Scotland said at the scene that the lorry hit several pedestrians as it careered along the road.

He sought to reassure people saying: "It's a road traffic accident, nothing more sinister."

Mr Carle stressed: "For now it does not look to be a criminal or deliberate act that has taken place here this afternoon, but we need to have time to investigate it."

He said that it appeared "at least" seven people had been seriously injured but warned that "that number may rise"

The driver of the bin lorry has also been taken to hospital and is receiving treatment, the officer said.

But in the wake of speculation that the driver had collapsed at the wheel of the lorry, Mr Carle said he could not comment on what he was being treated for.

He told how police "will be here now for many hours and throughout the night as we investigate the scene and eventually as we recover the dead".

Mr Carle said: "It's difficult for all the emergency services but particularly for those people who have been in Glasgow today shopping and getting ready for Christmas. There will be a lot of distressed people and certainly the city will need to come round those people that have been traumatised by the incident.

"But our officers, the ambulance officers, the fire officers, the city council officers they are all working together as quickly as possible to bring the scene to a conclusion."

He stated: "It is a road traffic collision with multiple fatalities, it's a terrible incident, but we don't believe there is anything at this juncture that is sinister about the accident.

"We have the road closed off from Ingram Street and Queen Street to George Square. We are currently starting a joint investigation with the criminal investigation department as to what has happened here this afternoon."

Mr Carle said that at "about 2.30pm a Glasgow City Council bin lorry was travelling north on Queen Street outside the Gallery of Modern Art when it was in a collision with a pedestrian".

He added: "The bin lorry then has continued north on Queen Street, it would appear to have gone up on the footway and there have been a number of other pedestrians it has collided with."

Reports suggested the lorry first struck pedestrians queuing at the Gallery of Modern Art (GoMA), more than 100 yards from the Millennium Hotel.

Police Scotland have set up a number for anyone who has concerns that their family and friends may be involved in the incident which is 01786 289070.

Queen Street Station remains open and a spokesman said there was no disruption to services currently.

A Scotrail spokesman said: "Services are running and we're asking people to use North Hanover Street and Dundas Street entrances until further notice."