KABUL, Sept. 11 (Xinhua) -- Four police officers and at least 87 militants have been killed in clashes and airstrikes in two Afghan provinces, authorities said Tuesday.

In southern Kandahar province, Afghan security forces backed by Afghan Air Force repulsed a massive Taliban attack on Maywand district Monday night, killing 57 militants and injuring 16 attackers, Gen. Abdul Raziq, provincial police chief, told Xinhua.

The militants tired to overrun the district, west of provincial capital Kandahar city.

Four police officers were also killed and 11 police injured while seven militants' vehicles were destroyed during the fighting, the police official added.

In addition, 30 militants were killed and 16 others injured following a cleanup operation launched by Afghan security forces and U.S.-led NATO coalition forces' airstrikes in Baghlan-e-Markazi district of northern Baghlan province, an army spokesman at the region, Hanif Rezai, told Xinhua.

The raid and airstrikes were launched in retaliation for militants in the district where 20 army soldiers were killed and many others injured late Friday night.

Afghan security forces, backed by the coalition troops, have increased ground and air offensives against militants in the past few months as the country is preparing for parliamentary and district council elections slated for Oct. 20.

The Taliban militant group has yet to make comments.