KABUL (AFP) - Two Nato soldiers and two Afghan mine clearers have been killed in bombings in southern Afghanistan, while three policemen died in a clash with Taliban fighters, officials and Nato said. The two Nato casualties, from the International Security Assistance Force (Isaf), bring to 133 the number of foreign soldiers killed in the country this year, according to an AFP tally based on the independent icasualties website. Two Isaf service members were killed in an improvised explosive device attack in southern Afghanistan today, the alliance said in a statement. The force did not disclose the dead soldiers nationality. Two Afghan mine clearers were killed and two others injured Tuesday when their vehicle struck a roadside IED in southern Afghanistans Uruzgan province as they travelled to work, a local police chief said. The men were employees of the Mine Detection Centre, a non-governmental organisation established in 1989 to sweep landmines planted mostly during the Soviet occupation of Afghanistan. A Taliban spokesman, Zabihullah Mujahid, claimed responsibility for the blast and said they were targeting a military vehicle. Taliban insurgents also attacked a police post in the southern province of Ghazni late Tuesday, sparking a firefight that left three policemen and two militants dead, said provincial police chief Khial Baz Shirzai. Then on Wednesday, a civilian helicopter contracted by the US military was forced to land after coming under fire in northern Kunduz province. District chief Shaikh Saadi blamed technical problems, but an Isaf statement later said it was a precautionary landing and there were no casualties.