A Northern Irish police official has said that 8,000 officials and three surveillance drones will be brought in to protect President Obama and other visiting dignitaries during the J8 summit in June.

Leaders from the U.S., Britain, Russia, Japan, Germany, France, Italy and Canada will converge on Fermanagh from June 17-18 for what will be the biggest high-security event ever mounted in Northern Ireland.

On Thursday, Assistant Chief Constable Alistair Finlay told a Catholic Protestant board that his force would deploy 4,500 officers and 3,500 more will be drafted in from Britain. The board approved the purchase of three surveillance drones for the event at Lough Erne Resort, in Enniskillen Co. Fermanagh.

The terrorist threat is considered high for the international summit of world leaders which attracts protesters every year.

In March, the dissident republican group Óglaigh na hÉireann (ONH) took responsibility for a 60kg device, made from homemade explosives, concealed in a beer keys that was destined for the resort where the summit is taking place.

"We are aware of a range of groups who either jointly or individually might want to come together to cause some disruption," Chief Constable Alistair Finlay told the Impartial Reporter.

Chief Constable Alistair Finlay told UTV the surveillance drones will be able to monitor suspicious activity.

"They're unmanned aerial vehicles like large model aircraft," he explained.

"They can be used in the line of sight, small close-range drones that beam pictures back to enable police to see what is going on on the ground. They can be used in weather conditions where the helicopter maybe cannot operate and slightly closer to various places."

Gerry Kelly , Sinn Féin party spokesperson on Policing and Criminal Justice expressed concerns the the drones may lead to an invasion of privacy.

"One of my worries about them, not that they are technology that is needed but that the use of that technology," he told UTV.

"So there are issues with privacy, there are issues with what is the legislative basis that they are being used on. Who can use them? Can criminals get their hands on these items as well?"

President Barack ObamaTony Dejak, The Associated Press