Taliban fighters in the southern Afghan province of Helmand attacked a checkpoint with silenced weapons and hand grenades early on Tuesday, killing 12 policemen and stealing weapons and ammunition, officials said. But a provincial official said that it could be an insider attack as one of the guards was still missing, Reuters reported. The attack, in the provincial capital Lashkar Gah, underlined the threat facing Afghan security forces in the opium-producing province, where they struggle to match well-equipped Taliban fighters who now control several districts. The police killed in the attack had been pulled back from the southern Khanshin District that security forces abandoned last year. “In a separate incident, another 12 policemen were killed in the Marjah District of Helmand after an hour-long gun battle,” Taliban Spokesman Zabihullah Mujahid said. Taliban fighters now control most of Helmand, including areas in Lashkar Gah. Afghan security forces now control less than 60% of the country, according to US estimates, with the Taliban in control of about 10% and the remainder contested between government and insurgent forces.