The number of civilians killed in the Afghan war in the first half of 2011 rose 15 percent, the United Nations said Thursday, putting the year on track to be the deadliest in a decade. The disturbing rise in deaths came after the United States sent thousands of extra troops into Afghanistan and said levels of violence in the 2011 fighting season would be an indication of the extent to which it had worked. The annual mid-year report by the UN mission in the country said insurgents accounted for 80 percent of all deaths and that NATO troops were responsible for 14 percent of killings, with half of all casualties caused by bomb attacks. \"A shift in the tactics of anti-government elements increased the severity of (their) attacks on Afghan civilians,\" the country\'s UN human rights director Georgette Gagnon told a press conference in Kabul. \"We saw the trend going the wrong direction.\" The report said heightened conflict in the traditional fighting areas in the south and southeast, and the spread of the insurgency to parts of the west and north, meant \"civilians experienced a downward spiral in protection.\" The latest figures come two days after the shock assassination of President Hamid Karzai\'s younger half-brother in his home in the southern city of Kandahar, one of the war\'s most bitter battlegrounds. The United Nations \"documented 1,462 civilian deaths in the first six months of 2011, an increase of 15 percent over the same period in 2010.\" According to the world body, the deadliest year on record in the current Afghan conflict, which began when US-led troops in 2001 invaded to bring down the Taliban regime, was in 2010 with the deaths of 2,777 civilians. In the first half of 2010, the United Nations reported 1,271 deaths. It attributed the rise to a wide range of increased violence, including a greater use of improvised bombs, suicide attacks and targeted killings, as well as more ground fighting and a rise in casualties from NATO air strikes. The Taliban were responsible for the vast majority of civilian casualties in an increase of more 28 percent on last year. NATO reduced the number of deaths it was responsible for by nine percent, and most were blamed on air strikes, mostly by Apache helicopters. The UN representative in Afghanistan, Staffan de Mistura, said it had been in touch with the Taliban over its role in killing civilians. \"What we need from them is a factual change or in other words a reduction of indiscriminate civilian casualties,\" he said at the press conference. \"They (Taliban) will not like this report, they will complain about it,\" he said, as he appealed for reduced violence during the holy fasting month of Ramadan due to begin across the Islamic world in two weeks\' time. The insurgent group last month condemned as \"propaganda\" UN data that blamed them for the deaths of more than 300 people in May, the deadliest month for civilians since it began tracking casualties in 2007. The United Nations said civilian deaths from improvised explosives devices (IEDs) increased 17 percent from the same period in 2010, making IEDs the single largest killer of non-combatants in the first half of 2011. It also said the number of targeted killings of Afghan security and government personnel across the country rose to 190 from 181 in the same period in 2010. Controversial night raids that US-led forces mounted to take out insurgent leaders accounted for two percent of civilian deaths, a slight decrease on the first half of 2010. \"However, resentment regarding these raids grew among the Afghan population,\" the report said. \"Violent demonstrations sometimes followed night raids and led to deaths and injuries of civilians,\" it said.