KANDAHAR (Reuters) Fifteen Afghan civilians died when their vehicle hit a roadside bomb in southern Afghanistan and seven road construction company employees were killed in an airstrike in an eastern province, authorities said on Saturday. The deaths were the latest in an upsurge of violence that has made this year the deadliest for both Afghans and foreign troops since the 2001 overthrow of the Taliban. There was also a suicide bomb attack on Saturday in northern Kunduz province, one of several areas that were relatively peaceful for many years but where the insurgency is now spreading fast. It is also used as a springboard to launch other attacks. The attacker was driving a police vehicle and targeted an Afghan National Army convoy, wounding five soldiers and three women who were in the area, said Char Dara District Chief Abdul Wahid Omakheil. Taliban spokesman Zabihullah Mujahid said the group carried out the attack. The 15 civilians were killed on Friday in the Khan Neshin district of Helmand province, said provincial spokesman Dawud Ahmadi. No further details were available. It was a newly planted mine, said Ahmadi. The road construction company employees were killed in eastern Paktia province in an airstrike by the NATO-led International Security Assistance Force (ISAF) overnight, said Paktia Deputy Governor Abdur Rahman Mangal. He said the employees were in roadside tents near the Paktia provincial capital of Gardez. No further details were available. The company had recently begun its operations, Mangal said. An ISAF spokeswoman said they were looking into the incident but declined further comment. Last month, NATO leaders agreed to hand control of security in Afghanistan to Afghan forces by the end of 2014 and said the NATO-led force could halt combat operations by the same date if security conditions were good enough.