The English Ministry of Defense (MoD) have revealed that a Royal Navy submarine was responsible for dragging an Irish fishing boat backwards at speed off the County Down coast.

On April 18, the fishing trawler Karen was dragged backwards for 18 miles at 10 knots an hour before the ship’s captain, Paul Murphy, told his crew to cut the wires connecting the net to the boat, losing his equipment but not before significant damage was suffered by the vessel.

Murphy has since said that his crew were lucky to escape unharmed and that $15,400 (£10,000) worth of damage had been inflicted on the boat.

When the incident was initially reported, the MoD claimed that it could not have been caused by an English sub as there was as there were none within 150 miles of the fishing boat at the time. Royal Navy vessels are also required to surface if they become tangled with fishing nets.

It was speculated at the time that it may have been a Russian sub in the area that was responsible for the collision.

"There was no doubt in my mind it was a submarine,” Murphy told RTÉ Morning Ireland.

“Having a lot of experience in this job it's the only thing that could be under the sea that could pull a big boat like this backwards at ten knots. That's when we knew we had a submarine but whose submarine was the question."

Sorry, it was us all along! Royal Navy admits one of its submarines damaged an Irish trawler... and

— JUST GEOFF official (@geoffkernow) September 8, 2015

Ardglass trawler: MoD admits submarine dragged fishing boat, causing '£10,000 of damage'

— Belfast Telegraph (@BelTel) September 7, 2015

The MoD have since admitted to parliament and to Murphy, however, that the damage was caused by a Royal Navy sub.

Armed Forces Minister Penny Mordaunt made a written statement to the British parliament stating: "The incident, the delay in identifying and addressing the events on that day, and their consequences are deeply regretted.

"This incident occurred because the submarine did not correctly identify the Karen as a fishing vessel with nets in the water, and thus did not give her the berth she would otherwise have had.

"Moreover, had the submarine been aware of the incident at the time, which it was not, then the protocols in place under the code of practice for submarine operations in the vicinity of fishing vessels would have required the submarine to surface and remain on scene while the matter was investigated."

In June, Mordaunt had claimed that the Royal Navy had "confidence that no UK submarine was involved".

The ministry informed Murphy of the new information through a letter received on Monday September 7, apologizing for the “frightening incident” and telling him they would be in contact to discuss further compensation.

Northern Ireland's Agriculture Minister Michelle O'Neill has questioned the MoD’s dealings with the incident, asking why it took so long for their to accept responsibility.

"Why does it take the MoD almost five months to come clean and admit what it has done?,” she questioned.

"We were told there was no allied submarine within 150 miles of the incident.

"We were led to believe this was an unsanctioned action by an unidentified nation."

Skipper Paul Murphy wants an apology in person after Royal Navy says submarine caused damage to Karen @bbcnewsline

— Claire Graham (@JournoClaire) September 7, 2015

Just raised the Royal Navy/Karen fishing vessel/submarine activity in the Irish Sea in the House of Commons 2day. Compensation required.

— Margaret Ritchie MP (@MRitchieMP) September 8, 2015

The boat’s skipper admitted that there were times he questioned his own sanity when thinking about the incident.

"Everyday we were going out and panicking about it. It really affected my fishing because I wasn’t able to go to places where I wanted to go,” he said.

“It's only the last couple of weeks that I've been able to venture back to the spot where it happened and that's where the good fishing is. So it's affected myself and my crew big time."