G8 summit will put Northern Ireland under security lockdown Parts of Northern Ireland are to be placed under effective lockdown during the upcoming G8 summit, with 3,600 officers being sent from Britain to bolster the police presence amid fears of widescale protests. An extensive array of security measures is being put in place for the two-day event - including a giant new security fence which stretches for miles - with authorities warning of major disruption at the summit venue in rural County Fermanagh and in other parts of the country. The battery of precautions will affect many facets of life, including the international airport, roads and schools. Vehicle checkpoints are to be reintroduced on a scale that has not been seen in Northern Ireland for many years. In addition to the summit itself, US President Barack Obama is to visit Belfast for what the White House describes as an opportunity "to highlight the hard work, dialogue, and institutional development the people of Northern Ireland have undertaken together." The summit and the presidential side-trip will together require one of the biggest security operations ever seen in Northern Ireland. There will also be a cosmetic side to the exercise, with about £300,000 being spent on prettifying the facades of dilapidated and derelict buildings. Several companies have been hired to remove chewing gum from pavements. South of the border, the justice minister, Alan Shatter, has warned that Irish mobile phone providers could be asked to cut their signals during the summit to ensure that republican dissident groups cannot use them to trigger bombs. "It is possible that terrorist groups may try to use the occasion of the summit to, at the very least, garner publicity for themselves," he said. This is not to ignore the very real danger of the loss of life if such a device were successfully detonated. He said mobile phones may have been used to trigger the devices which exploded at the Boston Marathon in mid-April. North of the border, police have deliberately been stepping up visible security for some months, concentrating more officers in the area around the summit venue. A spokesman said: "There has been an incremental increase in the policing footprint. We have gradually increased that and it's running at a higher tempo now. The approach of the authorities has been to advertise how extensive the security precautions are, in an attempt to emphasise to dissident republicans that any attempts to disrupt the proceedings would be pointless. Police have estimated that many thousands of political protesters could be active. While the authorities have said lawful and peaceful protests will be allowed, hundreds of temporary holding cells are being prepared in prisons and former army barracks. The new security fence will surround the Lough Erne hotel in Fermanagh where the summit will be held, with special marine units patrolling the local lakes and rivers which will provide a natural moat around the venue. Some hospital medical procedures are being postponed , while construction work on many main roads across Northern Ireland is to be halted for more than a week. With A-level and GCSE examinations due to be held at the same time as the summit, schools have been instructed by the Department of Education to prepare plans for any potential disruption. An official memo has warned that "exceptional circumstances may arise, at short notice, where schools will need to close." Meanwhile, houses in the vicinity of the summit hotel are being advertised for rents of about £3,000 a week. One is on offer for £12,000.