Irish police believe that up to six men were involved in the gangland hit

David Byrne, 33, was shot by the men during the boxing weigh-in in Dublin

One of the gang was dressed as a woman wearing a long blonde wig

Two hitmen have been pictured as they stormed a hotel dressed as police

Irish police are hunting a man dressed as a woman who was part of a six-man squad who gunned down a major Dublin drug dealer at a weigh-in for a boxing match on Friday afternoon.

The killer was photographed removing their blonde wig as they ran through the car park of the Regency Hotel in Whitehall, on Dublin's north side following the shocking of gangster David Byrne, 33.

The suspect, was wearing a long black jacket, blonde wig and black boots while carrying a semi-automatic handgun. He was followed by a man wearing a flat cap and tracksuit, who was also armed.

This is the shocking moment a gunman dressed as a woman, left, ran from the scene of a gangland assassination in Dublin where a major drug dealer was gunned down in a busy hotel on Friday afternoon

The two suspects, pictured running away from the Regency Hotel in Whitehall, Dublin were armed with semi-automatic handguns as part of the murder squad that shot dead senior gangland kingpin David Byrne

Gardai believe up to six men, including these two assassins dressed as police carrying Romanian-made AKM assault rifles, were part of the squad which murdered David Byrne on Friday afternoon

Witnesses mistook these two killers, who had 'Garda' stenciled on the back of their tactical vests for genuine police officers as they searched for David Byrne, who was a senior member of the Christy Kinahan gang

Two of the gang were photographed wearing SWAT-style police uniforms with metal helmets and tactical vests carrying Romanian-made AKM assault rifles.

Dublin gangster David Byrne, 33, was 'riddled' with bullets as he stood by reception in the Regency Hotel by the gang.

Several eyewitnesses mistook two of the gang for genuine police officers as they had 'Garda' - the name of the Irish police - on the back of their tactical vests.

The gang escaped in a grey Ford Transit van which was found burned out nearby. The gang firebombed the vehicle to destroy any forensic or DNA evidence linking them to the crime.

Two of Byrne's associates were also injured in the shooting. Sean McGovern, 30, from Crumlin and Aaron Bolger, 25, from Tallaght are both recovering in hospital following the attack.

The body of David Byrne lies slumped against the hotel reception desk after he was gunned down during the boxing weigh-in in Dublin yesterday

It's believed members of the Christy Kinahan gang - to which Byrne (pictured) was aligned - were the targets

Police today released this image of a grey van they say the group of six hitmen used to escape the scene. They have asked anyone who may have seen it in the past few days to contact them

The gang are believed to be a revenge squad operating in response to a murder last year which sparked fears underworld tensions between two powerful Irish gangs have erupted into all out war.

Police now believe six men were involved in the attack, including three that were dressed as police officers who stormed the hotel.

Two more, one of which was disguised as a woman, guarded the front steps while a sixth operated as the getaway driver.

Hotel owner James McGettigan told the Sunday Independent that he tried and failed repeatedly to ring the emergency services during the assassination.

He said he tried to ring 999 three times and failed. Instead, he called a Garda friend on his mobile.

Mr McGettigan saw the gunman open fire on Byrne in the hotel's reception.

He said: 'He was shot three times, twice in the body and once in the head. These guys made sure he was killed. There was smoke coming out of his body.

'I ran out towards the exit and decided to go into a small residents' lounge. I saw a girl on the way there and I said to her: "Ring the guards immediately." She said: "The guards are here already." That's how much confusion there was.'

David Byrne, pictured, was a senior member of a drugs gang headed by Dublin born mob boss Christy 'The Dapper Don', and is suspected of being one of the largest cocaine dealers in Europe

Aaron Bolger, pictured in the white tee shirt in a bar in Puerto Banus, Spain, was injured in Friday's shooting

The hit was targeted. It's believed members of the Christy Kinahan gang - to which Byrne was aligned - were the targets.

A witness in the hotel at the time of the attack told The Irish Sun one of the killers, dressed as a woman, brushed past him moments prior to the shooting.

He said: I saw a man dressed as a woman. She walked past me but bumped into me. I thought she was a transvestite. Little did I realise it was a man.'

Another witness told the Irish Independent the two gunmen entered the building and began shooting - while another two, including the man dressed as a woman - cornered those fleeing on the steps outside.

The witness explained: 'I heard a man dressed as a woman say "he's not f****** here, I can't find him." He was wearing a long blonde wig.

'The other guy roared back "get the f*** out of here" just as the other two came out the front door and came out past me and went down to the silver transit van and they all bundled into this van.'

One of the boxers, pictured, was in the middle of his weigh-in in Dublin just as the gunmen opened fire

Amid chaotic scenes, the boxer and audience members fled through an emergency exit to flee the gunmen

Eyewitnesses ran for the exits as the two killers, one dressed as a woman, opened fire on the victim

Several families were near the stage when the gunmen opened fire killing one man and injuring two others

Police sources told the paper it was clear the gunmen had planned to murder several members of Kinahan's syndicate, describing it as 'an unprecedented escalation of a feud that has now become an all-out war'.

Gardai Chief Superintendent Barry O'Brien said it was a 'particularly nasty incident' that had involved 'severe weapons'.

He said: 'Two individuals were wearing what was described as police-type uniforms. In that regard it was described as a SWAT uniform with metal helmets, similar to what you see on crime dramas.'

A third witness told The Irish Sun: 'They were wearing masks and helmets. The weapons were massive, like the ones the IRA used to use.'

The shooting is likely to have been in retaliation for the murder of Gary Hutch in September in Spain.

Mr Hutch, nephew of the notorious Gerry ‘The Monk’ Hutch, is believed to have been murdered by the powerful Kinahan crime gang after he stole money from them.

He used to work for the Kinahans. Police believe yesterday’s attack was carried out by criminal associates of the Hutch family who ‘swore revenge’ against the Kinahans for the murder.

The Kinahans are involved with promoting boxing events and have established their own gym in Spain. Daniel Kinahan frequently travelled to boxing events in Ireland.

Bryne was at the Regency Hotel in Dublin to witness the weigh-in of Jamie Kavanagh who was due to fight for a European title tomorrow.

Dramatic footage shows the moment the gunfire erupted, with a girl heard crying: 'Daddy, what's going on? Daddy help me,' as the gunshots continued to ring out.

Police removed the body of David Byrne, pictured, who was shot dead in a gangland attack in Dublin yesterday

The slain drug dealer was a major player in the cocaine scene in Dublin and was based on the city's south side

Irish police believe this burned-out Ford Transit Van was used by the killers as a getaway vehicle

Unknown gunmen brandishing handguns and wearing 'police-style uniforms', entered the lobby and started shooting, witnesses said

Gardai outside the Regency Hotel in Dublin after one man died and two others were injured following a shooting incident at the hotel

At least two of the gang are believed to have been armed with a type of Kalashnikov assault rifle while the remainder brandished handguns.

The gang escaped in a van which was found burned-out a short time later.

Police today released a photograph of a grey van which they believe the killers used to escape the scene.

Assistant Commissioner Jack Nolan asked has asked anyone who saw the van in the past few days to contact them.

He said: 'We know that there were a considerable number of people present in the Regency Hotel and we are appealing to them to provide any information they may have in relation to the shooting.

'We are also appealing to anyone who was in the area of the Regency Hotel between 2.00 and 2.45 pm, or anyone who was in the Charlemont Estate at that time is asked to contact Ballymun Garda Station on 01 666 4400 or the Garda Confidential line 1800 666 111.'

Video shows that amid chaotic scenes, one of the boxers on stage runs for his life as the gunmen open fire.

The two other men injured in the attack are close friends with Byrne and spend much of their time in Spain.

They have been named locally as Aaron Bolger, 26, from Killinarden, Tallaght, Dublin, and Sean McGovern, 30, from Captain’s Road, Crumlin.

Witness Mel Christle, president of the Boxing Union of Ireland, was standing on a podium where the last of the boxers weighing in had just stood down when he heard gunfire erupting outside the room.

He said: 'There was a horrific cracking noise, in front of me, out of the banquet room - it was a place called the Regency Suite.

'There was an incredible noise out there, and that is where I saw a body, a corpse, lying literally at the edge of the reception desk.

'So I'm sure he [the victim] was trapped - he was riddled.'

Mr Christle said one of the gunmen was dressed up as a woman and aged in his early 20s.

The boxing chief was adamant the attackers were not targeting the boxers gathered for the weigh-in, but other individuals who were hit in the hotel reception.

Byrne's murder has been linked directly to the shooting of Gary Hutch, who was killed in Spain in September

Jamie Kavanagh, left, who was due to fight today, was the son of Gerard 'Hatchet' Kavanagh, right, who was murdered in Spain in September 2014. Kavanagh was an enforcer for the Dapper Don Christy Kinahan

He said there was panic as some people dived for cover when they realised what was happening.

'I actually saw the sheer fear that will live with them for a long, long time,' he said of those who witnessed the shooting.

'It actually touched me, how afraid - I'm sure adults were afraid, but my God, the children couldn't believe what was going on.'

The gunmen fled the scene in a van, which was later found set alight nearby.

Kevin McAnena, a sports reporter who was covering the weigh-in, said one of two gunmen dressed in Garda-style uniforms pointed a 'big, massive' gun at him while he sought cover in the lobby in the heat of the attack.

'I jumped over the reception desk, I think I smashed the vase on my way, then the gunman came over to reception, looked down at me and pointed the gun at me, and I shouted, I was shouting even before he came over "don't shoot, don't shoot",' he said.

'[The gunman] said something to me but I don't know what he even said, I can't remember at this point, I just know I've never felt terror like it, I was really, really scared and then after that it was just silence.'

Gerard 'Hatchet' Kavanagh, right, was a key enforcer for the Dapper Don Christy Kinahan, left

Jamie Kavanagh tweeted following the shooting that he was 'lucky' after the horrific scenes

Mr McAnena said he saw a gunman firing into a victim's leg.

'The man I saw being shot in the leg, is the man who is now dead - he was no more than six foot from me,' he said.

'The gunshots I heard after I jumped over the receptionist's desk were probably the gunshots that finished him off.

'That same gunman looked over at me before pointing the gun at me, telling me, I think he said "get up" or "go away" or something like that."

Mr McAnena said he heard two shots outside the hotel and at least three more inside.

'They were big, massive guns - gardai have told me since they were AK-47 rifles,' he added.

'It was just so surreal, it happened so quickly. I remember thinking if he just shot him without looking, then he is going to shoot me.'

There were approximately 200-300 people at the weigh-in when the shooting started.

Two detectives attending the scene said it was too early to specify any motive, but cited the deadly feuding between gangland factions as one possibility.

A headliner in Saturday's boxing bouts was Jamie Kavanagh, whose father - a convicted drug dealer - was shot to death in Spain in 2014. He was an enforcer for the Kinahan syndicate.

The younger Kavanagh was due to fight Joao Bento for the vacant WBO European lightweight title.

The fight's promoters have announced that tomorrow's bout has been cancelled as a result of the murder.

Forensic experts scoured the carpark of the Regency Hotel looking for any evidence of the assassination

Irish police were located near the hotel at the time of the shooting as they were aware that several major gangland figures were planning to attend this afternoon's weigh-in in the Regency Hotel in Dublin, pictured

Irish police removed this Audi RS8 from outside the hotel this evening following the earlier murder

Irish police released a statement following the shooting: 'The incident occurred at about 2.30pm on Friday 5th Feb. Emergency services responding to reports of a shooting discovered three men, all in their 20s or 30s, injured at the scene.

'One of these men was subsequently pronounced dead. Two others were removed to The Mater and Beaumont hospitals with possible gunshot wounds.

'The scene is sealed off and a technical examination of the area is expected to take place. Gardaí are appealing for anyone who was in the area of the Regency Hotel or may have information, to contact them at Ballymun Garda Station on 01 666 4400.'

The Irish Prime Minister Enda Kenny, who is currently seeking re-election tonight blamed the shooting on rival Dublin drug gangs.

Chief Superintendent Barry O'Brien who is leading the investigation said: 'One [of the attackers] is described as possible being a male disguised as a female wearing what was described as a blonde or auburn wig.