IT was meant to be a happy celebration ahead of one man preparing for his dream wedding.

But what was supposed to be the perfect lads' weekend away descended into a nightmare forcing a plane to make a dramatic unscheduled landing and leaving six of the group facing fines of nearly £20,000.

The group were on a Ryanair flight bound for renowned stag party destination Bratislava in Slovakia, below.

Daily Echo:

But it was dramatically grounded after rowdy behaviour allegedly broke out on board involving a group of men celebrating a Southampton groom’s stag do.

The 12-strong bachelor party were believed to be marking the forthcoming marriage of 26-year-old Joshua Mariner to fiancee Abi Whitmore.

Just hours before take-off they had posted pictures of themselves on social media raring to go.

The pictures were taken in a bar just hours before boarding the flight with them all wearing T-shirts with the groom’s face printed on the front.

The party had been aboard a 170-passenger flight travelling from London Luton airport to Bratislava, named the best value city in Europe to have a stag party.

But their behaviour caused the pilot to land the plane unexpectedly in the German capital of Berlin en route (see map below) and eject six members who allegedly became unruly on the flight.

Daily Echo:

Reports in Germany say the men became aggressive when they were refused alcohol – there are even allegations that one of the party stripped naked while on the flight.

Local police said the drunken Britons, aged 25 to 28, were met by officers upon landing at Schoenefeld airport near Berlin at 8.30pm on Friday.

They were taken into custody and held but were then later released.

There were also conflicting reports as to whether the groom himself was among those taken off the flight.

A German police statement said he had been held but others posting on the Daily Echo website said that he had remained on the aircraft and continued his journey to Slovakia.

Each of those arrested now faces a fine of up to 25,000 euros (£19,700) for breaking Article 20 of Germany’s Aviation Security Act.

That states that pilots can take actions against someone who is deemed to be a danger or cause damage to the plane. They could also face a civil claim from Ryanair.

The plane’s remaining 164 passengers, including the other half of the stag do not involved in the incident, then continued their journey to Slovakia.

Alexander Koller, a passenger on the plane, was quoted as saying: “The passengers were a disgrace – by the way, [they were] not the only drunken, obnoxious people on this flight by any means.

“The fact that they were allowed to board at all after making a huge nuisance of themselves in the departure hall at Luton and being so drunk that some were struggling to stand, was an even bigger disgrace.

“It was a total failure by Ryanair’s ground staff at the gate and by the cabin crew who should have spotted them. This was not hard [as] they were extremely loud and obnoxious whilst boarding and finding their seats.”

Many of the party are understood to be from Southampton and had known Joshua – who is a self employed ceiling and partitions specialist – for years, some of them having attended the same school Bitterne Park Secondary School.

One of the party posing in the photograph is even to understood to have missed the flight after being separated from his schoolfriends ahead of take-off.

Last night the friend’s mother told the Echo “I am glad that he didn’t get on – it was just fate that he missed it.

“He phoned me to say he was getting the train back. But some of the others got there and my son just knows that Josh had a nice evening.

“What I don’t understand is why they let them on in the first place if they had noticed they had had a drink? Why didn’t they turn them away unless they weren’t that bad.”

The incident sparked a fierce debate on the Echo website where one reader called Fallontina wrote: “These boys are not chavs thank you very much.

“The ones I know are highly regarded within their community and social group. They are well liked, hardworking, kind, courteous and respectful to those around them.

“Making assumptions about these people based on a single incident is uncalled for. Who are we all to judge? I think you’ll all find that there are always two sides to a story.”

And another, who called himself South12, wrote: “The groom remained on the plane and is currently enjoying his stag apart from two people.”

He said the incident only involved two members of the group before adding: “I am a friend and am looking forward to the wedding that is still very much happening.”

A Ryanair spokesman confirmed the flight had diverted to Berlin after a number of passengers became “disruptive” and had been detained at the airport.

He said: “We will not tolerate unruly or disruptive behaviour at any time and the safety and comfort of our customers, crew and aircraft is our number one priority.

“This is now a matter for local police.”

A statement from the German Federal police said police boarded the plane and handed cautions to six men removed from the flight by the captain and said: “During the flight, six of the twelve men disrupted the safety on board and did not follow the instructions of the cabin crew.

It continued: “The police officers issues the 25 to 28-year-old men cautions under the Aviation Security Act. This is punishable with a fine of up to 25,000 Euro, and a civil claim from the airline might follow.

“After establishing their identities, the six young men, which included the bachelor, the federal police left.”

A spokesman for German police said an investigation into the incident was continuing but the men had released from custody and added it is unlikely they will be ordered to return to Berlin.