At least 17 Afghan policemen were killed on Saturday when dozens of Taliban militants stormed their outpost in the country's volatile south, the latest attack of an increasingly deadly summer fighting season.

The pre-dawn raid occurred in Helmand province as the Taliban intensify their countrywide summer offensive despite repeated government attempts to reopen peace negotiations.

"Dozens of armed Taliban attacked a police checkpoint in Musa Qala district of Helmand," provincial police chief Nabi Jan Mullahkhil told AFP.

"In the attack, 17 police forces were killed, and three others were wounded."

Omar Zwak, the spokesman for the Helmand provincial governor, confirmed the death toll from the raid that occurred just after midnight and lasted several hours.

The Taliban claimed responsibility for the attack, saying they seized several weapons, ammunition and other military hardware from the checkpost.

Afghan authorities have repeatedly tried to jumpstart talks with the Taliban in the hope of ending the 13-year conflict, but the militants have set tough conditions, including the withdrawal of all foreign troops in Afghanistan.

Afghan security forces, many of them poorly equipped, have increasingly borne the brunt of the fighting around Afghanistan.

In early May Taliban militants killed at least 13 policemen after storming security outposts in the remote mountainous province of Badakhshan.