An Afghan official says a string of Taliban attacks have killed 12 policemen in the increasingly volatile southern Helmand province the previous night.

Hismatullah Daulatzai, head of police for the greater Helmand zone, says the attacks were coordinated and targeted police checkpoints in Gereshk district on Sunday.

Daulatzai said Monday that seven policemen were also wounded in the attacks and seven others are missing, presumably abducted by the Taliban.

The 15-year insurgency has intensified across the south as the Taliban concentrate their war on Helmand, Kandahar and Uruzgan provinces.

The fight in the southern, opium poppy-producing region is led by Mullah Yaqoub, the son of Taliban founder Mullah Mohammad Omar. Mullah Omar's successor was killed in a drone strike this month and Mullah Haibatullah Akhundzada was named to replace him.