Twelve policemen and a child were killed Sunday when a suicide car bomber struck outside police headquarters in the southern Afghan city of Lashkar Gah, officials said. The attack came days after control of security in the city, the capital of Helmand province, passed from British to Afghan forces as part of a process that will see all foreign combat troops leave Afghanistan by the end of 2014. Some experts question the ability of Afghan soldiers and police to protect their country against attacks from the Taliban, who claimed responsibility for the latest blast, and other insurgents. The interior ministry confirmed the death toll and vowed the attack would not prevent the police from battling the Taliban, leaders of a 10-year insurgency raging across the country. \"Twelve Afghan National Police members and a child were martyred and 12 other Afghan National Police members were wounded (along with) two civilians,\" it said in a statement. \"The Ministry of Interior strongly condemns the insurgents (behind) this un-Islamic and inhumane action and such attacks will never weaken the determination of Afghan National Police.\" The blast happened at around 8:30 am (0400 GMT) in front of the heavily-secured police headquarters as Afghan police left to go on a patrol, a statement from the governor\'s office added. In a statement on their website, the Taliban claimed responsibility for the attack in Helmand, one of the most dangerous provinces in Afghanistan and a key focus of the war for international troops. \"A large number of policemen were gathered and a hero of the Islamic Emirate of Afghanistan struck and exploded his vehicle laden with explosives,\" the statement said. The attack came as an official said 10 Afghan security guards were killed in central Afghanistan Saturday in an attack on a convoy carrying supplies to international troops. The convoy was ambushed by insurgents in the restive province of Ghazni, triggering an hour-long battle, governor\'s spokesman Maroof Ayubi said. The Taliban also claimed responsibility for that attack in a statement. Anti-government forces frequently target convoys supplying the foreign and Afghan militaries. The Lashkar Gah blast comes amid ongoing concerns over the ability of the Afghan security forces, which are receiving huge sums of money from the international community in a bid to build them up. There are currently at least 126,000 police in Afghanistan and thousands more are being trained up in programmes financed by countries in the NATO-led International Security Assistance Force (ISAF). However, they have faced allegations of corruption and also struggle with factors including low literacy rates among recruits. The Afghan police and army are frequently targeted in attacks by the Taliban and other insurgents in a bid to undermine President Hamid Karzai\'s government in Kabul. There are currently roughly 140,000 foreign troops in Afghanistan, of which about 100,000 are from the United States. Some nations including the United States have already started withdrawing troops as part of a phased drawdown ahead of the 2014 deadline. The Helmand attack follows a spate of assassinations in southern Afghanistan in recent weeks, including that of the president\'s powerful half-brother, Ahmed Wali Karzai, in neighbouring Kandahar province. Karzai was killed by his bodyguard earlier this month, while Kandahar mayor Ghulam Haidar Hameedi was assassinated last week by a suicide bomber who hid explosives in his turban.