QALAT, Afghanistan, Sept. 18 (Xinhua) -- At least four Afghan policemen and 20 militants were killed during clashes between security forces and Taliban militants in Afghanistan's southern Zabul province, a local official said Tuesday.

"Taliban militants launched a coordinated attack on police checkpoints in Arghandab district of Zabul Monday night. They faced fierce resistance of security forces," Gul Islam Sayyal, spokesman for the provincial governor, told Xinhua.

The violence has been on the rise as Afghan security forces struggle against a surge in attacks by militants at a time when the country is preparing for parliamentary and district council elections slated for Oct. 20.

Taliban militants did not make comments on the report so far.