
It has been a night of wild celebrations and drunken mayhem across Britain as New Year revellers welcomed 2016 by hugging police cars, rolling around in the street and, in some cases, losing their trousers.

Millions of party-goers packed out pubs and clubs, with some braving freezing temperatures, while in the Welsh town of Aberystwyth one woman was seen lying in the road as she and a friend waved goodbye to 2015.

Another was pictured wrapping her arms and legs around a police car.

Revellers were also seen looking a little worse for wear in Swansea, vomiting outside takeaways, being helped off the pavement and having to be carried away as their trousers fell down.

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Helping hand: A woman is led along the street by two of her friends after celebrating in Newcastle city centre

Racy: A woman crosses the road wearing a skimpy outfit on Birmingham's Broad Street, left. Right, a woman in Liverpool

Celebrations: Revellers took to the streets of Aberystwyth, where one woman was pictured wrapping her arms and legs around a police car

Another man was seen being helped away by friends (left), while police detained one reveller whose trousers were falling down (right)

Winding down: Towards the end of the night a number of revellers in Birmingham took a seat outside one of the city's popular night spots

In Edinburgh a couple huddled up as temperatures plunged (left) and in Birmingham a reveller was taken away in an ambulance (right)

New Year excess: In the Welsh town of Aberystwyth one woman was seen rolling around in the street as she welcomed the arrival of 2016

One man was also seen with his jeans part way down as he was detained by police.

In London, a reveller was taken away on a stretcher while dozens more were tended to by the emergency services and temporary treatment centres. Some were handed blankets after braving temperatures below 0C in parts of the country.

There were a total of 48 arrests in the capital overnight, including four for drug possession, three for carrying offensive or bladed weapons and five for assaults on police officers.

Six people were also detained for public order offences, 11 for assault and one for sexual assault, the Met said.

West Midlands Ambulance Service, which put a record number of crews on duty, dealt with 1,629 emergency call-outs between 8pm on New Year's Eve and 4am on New Year's Day.

A spokesman said a man aged in his late teens was successfully resuscitated using a defibrillator after suffering a cardiac arrest outside a nightclub in Broad Street, Birmingham, shortly after 1am.

Thousands of people had gathered on the banks of the River Thames for a stunning midnight display featuring around 12,000 fireworks.

But it was what they left behind that was just as eye-opening, as the clean-up operation began in earnest to rid the streets of rubbish.

As revellers made their way home, one woman was seen carrying an inflatable Zimmer frame, while others had to help up friends who had fallen down.

The scenes were similar to that witnessed on 'Black Eye Friday', known as Britain's booziest night of the year. The final Friday before Christmas, it saw Britain's towns and cities descend into chaos as binge-drinkers hit the streets in their droves.

Police cells in Plymouth were full by midnight as officers dealt with incidents of violence, drunkenness and disorder on their busiest night of the year. And medics in Wales were forced to open a makeshift Accident and Emergency ward in the streets of Cardiff to deal with the fall out.

Streets of shame: One reveller in Swansea looked a little worse for wear as he was pictured vomiting outside a takeaway kebab restaurant

Falling over: A young woman is helped by a friend after tripping in the centre of Swansea, South Wales, during the New Year celebrations

In London, officers were seen standing over a reveller who was found laying on the ground after the capital's spectacular fireworks display

The collapsed man drew concern from his friends after laying down on the floor in the centre of London following the New Year festivities

The clean-up operation was swiftly under way in the capital (left) after rubbish was left strewn across streets following the festivities (right)

Night of excess: The emergency services were kept busy in the capital, with one man being taken away for treatment on a stretcher

Revellers were pictured heading home in central London in the early hours, with one woman seen carrying an inflatable Zimmer frame

An argument broke out between two women at a takeaway in Birmingham's Broad Street as revellers began winding down for the night

First meal of 2016: One group of party-goers tucked into a takeaway after a night of New Year celebrations in Birmingham city centre

Fall: In Birmingham, one woman had to be helped up off the floor by a friend as revellers continued to party long into the night (pictured)

On New Year's Eve, those in the capital were watched over by every available officer at the Metropolitan Police's disposal, including hundreds of firearms personnel, as European cities tightened security over fears of a Paris-style terror attack.

The Met Police confirmed the occasion was one of two events, along with Notting Hill Carnival, in which there was no holiday entitlement.

Force spokesman Superintendent Jo Edwards said the extra officers were for reassurance and the event was 'successful'.

She said: 'Our officers worked alongside stewards to support their operation and help people to get in and out of the event area safely and efficiently.

'Although the celebrations have drawn to a close, officers continue to work through the night to facilitate the clean up operation and bring the area back to normality in time for the New Year's Day parade.'

Today, more than 8,500 performers representing 20 countries will take part in the annual New Year's Day parade through London, again amid a large security operation.

Enjoying the evening: Party-goers were in high spirits in Birmingham as the celebrations to ring in 2016 ramped up as the night went on

Ambulance crews were kept busy, carrying away one woman in a wheelchair (left), while other revellers took to resting against walls (right)

Violence: Tempers flared in Birmingham's Broad Street as a fight broke out between several party-goers during the New Year celebrations

Party mood: Groups of happy young people were seen out and about on the streets of Aberystwyth as they celebrated the arrival of 2016

Relief: Around 75,000 people descended on Edinburgh for the city's Hogmanay celebrations, including two men in kilts who looked glad the night was over. One was sitting on a park bench while the other rested his head against a tree (pictured)

A man and woman help each other home after partying the night away in Edinburgh (left), where huge volumes of rubbish were seen (right)

Walking wounded: The clean-up operation got underway in Edinburgh, where tens of thousands celebrated with a street party. One man appeared to have injured himself after being pictured with concerned onlookers and a bandage wrapped around his head

The event, which includes marching bands, cheerleaders, clowns and acrobats, kicks off in Piccadilly and finishes in Parliament Square, taking in Lower Regent Street, Pall Mall, Trafalgar Square and Whitehall.

In Munich, German authorities declared a major terror alert over fears of an ISIS terror attack.

A foreign intelligence service had warned that between five and seven suicide bombers from the terror group had been planning on attacking the southern German city.

Two railway stations - Munich's main station and the Pasing station - were evacuated after indications of a planned attack which would target party-goers in the city.

A police spokesperson said that they had ‘reliable information’ that a group was planning to act as festivities were well under way on New Year’s Eve.

Arrested: Two police officers in Bristol detained a man in the city centre as excitement over the New Year festivities boiled over (pictured)

Ready to party: Revellers in fancy dress headed out for New Year's Eve in Bristol as people in the city welcomed in 2016 in style (pictured)

Tired: It was a long night for many as the festivities continued into the early hours. One man was seen sitting with his head in his hand

On patrol: On New Year's Eve, those in the capital were watched over by every available officer at the Metropolitan Police's disposal

Swift: Litter was piled into rubbish bags as clean-up teams across the capital worked through the night following a night of celebration

Outstanding: Fireworks in the capital have heralded the arrival of 2016 as revellers packed Central London near the London Eye

Blue is the colour: The celebrations went ahead as planned, despite a similar display in Brussels being cancelled due to safety concerns

In the Eye's shadow: Revellers in Central London dance ahead of the New Year celebrations on the banks of the River Thames last night

‘Actual lead that in #Munich a terror attack is planned. Please avoid crowd gatherings as well as the central train station and the Pasing train station,’ read the tweet.

Another tweet from the police read: ‘We note explicitly once again that we take the threat very seriously. Please remain alert.’

Across Europe, capital cities were on high security alert, with Brussels and Paris both scrapping fireworks for New Year's celebrations.

In Berlin, the police presence was stepped up at the Brandenburg Gate, where hundreds of thousands of people gathered for festivities. All large bags and backpacks were banned from the site of the huge street party.

Major security operations involving thousands of police were in place in other cities, including Sydney, Bangkok, Delhi and New York.