A roadside bomb attack killed three NATO troops in eastern Afghanistan, one of the deadliest flashpoints in the 10-year war against Taliban insurgents, according to a military spokesman there. NATO's US-led International Security Assistance Force (ISAF) did not release the nationalities of the troops or give further details of the incident, which happened yesterday. The deaths take to 561 the number of foreign troops killed in Afghanistan so far this year, according to an AFP tally based on figures from independent website iCasualties.org. A total of 711 foreign troops were killed in Afghanistan last year, the highest annual total since the US-led invasion in 2001 ousted the Taliban from power. There are about 130,000 international troops in Afghanistan fighting the Taliban-led insurgency, with 91,000 of them from the US.