New year celebrations: Revellers gather in London and across UK Published duration 1 January 2015

media caption Fireworks marked the start of 2015 in London and Edinburgh

Thousands of people have gathered across the UK to watch New Year's Eve fireworks to herald the start of 2015.

Some 100,000 revellers lined the River Thames in London for the first ticketed new year's display.

Huge crowds also took to the streets in Edinburgh and across Scotland for Hogmanay celebrations.

Celebrations were held across the world with fireworks displays in a host of major cities.

Shortly after midnight, Prime Minister David Cameron tweeted : "Happy New Year."

image copyright Reuters image caption Some 75,000 people were expected in Edinburgh for Hogmanay celebrations

image copyright Reuters image caption Revellers gathered in Princes Street, Edinburgh, to see in the new year

image copyright PA image caption In London, thousands gathered along the Thames to see the display

image copyright Getty Images image caption The display was accompanied by an electronic soundtrack and was followed by Auld Lang Syne

In London, a crew of more than 300 set off 12,000 fireworks as part of the annual display.

The display was counted in by a 10-minute digital countdown on the western facade of The Shard - the central London skyscraper - followed by lighting comprised of searchlights, strobes and a 2015 numeric graphic.

It was the first time the display has been ticketed, with revellers paying £10 to cover the costs of running the display.

It comes after an estimated 500,000 people tried to see the 2013-14 new year display, resulting in many being turned away for safety reasons.

Mayor of London Boris Johnson tweeted : "London's dazzling fireworks were a wonderful way to welcome in the New Year. Thanks to all who made it such a safe & fun event."

The Metropolitan Police said that by 06:00 GMT 90 people had been arrested in London, including 27 for being drunk and disorderly, 22 for assault, seven for sexual offences, six for drugs offences and two for possession of an offensive weapon.

The force said 4,000 officers had been part of the policing operation, while London Ambulance Service operations director Jason Killens said paramedics had also had a busy night.

"We're taking an emergency call every 10 seconds and we are expecting it to get even busier," he tweeted

Warm-up party

Elsewhere, West Midlands Ambulance Service said it had received more than 100 calls within the first 30 minutes of 2015, adding that "quite a few are alcohol related"

A spokesman said that between 20:00 GMT on New Year's Eve and 04:00 GMT on New Year's Day, handlers responded to 1,436,999 calls.

East Midlands Ambulance Service tweeted : "We've had over 340 calls in 1st two hrs. That's a new call every 21 secs!"

Edinburgh hosted an estimated 75,000 people at its Hogmanay street party and fireworks display.

Events were also held in Aberdeen, Inverness, Stirling and Stonehaven, while a warm-up party was held in Glasgow.

However, Hogmanay celebrations on Stirling Castle's esplanade had to be cancelled owing to high winds.

image copyright PA image caption A crew of more than 300 people set off 12,000 fireworks as part of the annual display

image copyright EPA image caption The display began as Big Ben chimed at midnight

image copyright PA image caption A giant 2015 was illuminated on The Shard in central London

image copyright PA image caption It is the first time the annual display in London has been ticketed

image copyright PA image caption Huge crowds gathered along Embankment in central London for the display