We stopped scores of dissident attacks in 2014, claims MI5 chief
The vast majority of dissident republican terror attacks are being foiled, the UK's top intelligence official has said.
More than 20 attacks were carried out in 2014, according to MI5 director general Andrew Parker.
But up to four times that number were thwarted by the security services, he revealed during a speech in London.
Mr Parker said the terror threat in Northern Ireland remained real.
"Whilst there has been great progress in Northern Ireland, dissident republicans continue to carry out terrorist attacks aimed at the police, prison officers and others," he said.
"There were more than 20 such attacks in 2014, most of which - thankfully - were unsuccessful.
"The key statistic is that for every one of those attacks we and our colleagues in the police have stopped three or four others coming to fruition.
"Northern Ireland experience teaches us that terrorist threats are enduring; that it requires sustained long-term effort and teamwork to counter them; and that it's unrealistic to expect every attack plan to be stopped, even where the perpetrators may in some cases have been on our radar for many years."
Dissident attacks foiled in 2014 include:
A suspected bomb discovered by police in Co Louth. Five men were arrested after the device was found in Kilcurry, north of Dundalk
A major operation in Newry which saw seven arrests by police investigating "violent dissident republican activity". Five are later charged with directing terrorism
A huge weapons find in Co Fermanagh. Police said a "significant" amount of explosives were found after buildings, vehicles and fields were searched at a farm in Kinawley.
However, the past year has also seen a number of successful attacks.
In May, a masked man claiming to be from the IRA threw a firebomb into the reception of the Everglades Hotel in Londonderry.
The hotel was evacuated and the device exploded a short time later when Army bomb experts were working to make it safe.
Dissidents also used a home-made rocket launcher to attack a PSNI Land Rover at Twaddell Avenue in north Belfast in November. It struck the vehicle but no one was injured.
In March, dissidents used a command wire to fire a mortar at a PSNI Land Rover on the Falls Road in west Belfast. A car containing a Filipino family was also caught up in the attack.
DUP MP David Simpson said Mr Parker's comments were "a sobering reminder" of the terror threat. He said a fully operational National Crime Agency (NCA) could help the fight against dissidents.
The NCA - an FBI-style crime body - is not operating in Northern Ireland because it has been blocked by Sinn Fein and the SDLP. Mr Simpson said the block was hampering the campaign against organised crime which helps fund terror gangs.
"These terrorist gangs must be tackled from every angle, and by cutting their source of funds it helps cut them off at the roots," he said.
"It would also ensure that vital resources are freed up within the local policing budget to assist with other priorities."
Mr Parker's speech also touched on the general terror threat to the UK. He warned the threat was increasing and the security services could not be expected to stop every plot but had thwarted three in recent months.