At least four Haqqani militants were killed in an airstrike in Afghanistan's Paktia province on Friday, officials said."Based on a confirmed tip-off, the airstrike was launched on outskirts of provincial capital Gardez on Friday morning. The sortie killed four militants of Haqqani terrorist group," according to a statement issued by the provincial government.Security forces and civilians did'nt suffer any damage in the strike which was launched by the NATO-led coalition forces in coordination with Afghan security forces, the statement was cited as saying by Xinhua news agency.A number of heavy and light weapons and ammunition were also destroyed in the raid.Haqqani network, a Taliban-linked militant group, mostly operates in eastern provinces and capital Kabul and has been responsible for high-profile attacks on security forces.The network, which was named as a terrorist group by the US in 2012, was yet to comment on the incident.The Afghan security forces, backed by the NATO-led coalition troops, have increased ground and air offensives against militants within the past a few months as the fighting season is drawing near in the country.Earlier in the day, the Taliban militant group announced the launch of a yearly rebel offensive against Afghan and coalition forces codenamed al-Fath.