NATO said Saturday that two of its soldiers were missing in Afghanistan amid claims by the Taliban that they captured the servicemen south of Kabul reported.
The soldiers left their compound in Kabul city on Friday afternoon and "did not return," the NATO-led International Security Assistance Force (ISAF) said in a statement.
A NATO source said they missing soldiers are Americans.
Taliban spokesman Zabiullah Mujahid said the two US soldiers were captured in Logar province, which borders Kabul. They were carrying weapons and communication kits when seized, he said.
Din Mohammad Darwish, spokesman for the Logar governor, said two US civilians were captured by the Taliban in Charkh district as they were heading to the southeastern province of Paktia on Friday afternoon.
"Our police forces stopped their vehicle and warned of the Taliban's presence in the area, but they did not listen," he said.
Darwish said local officials reported that the Taliban killed one of the hostages and took the other to an unknown location.
The ISAF statement said that the military dispatched vehicles and helicopters to search for the missing personnel and their vehicle, "and the search is ongoing."
Local officials and residents in Logar also said that military helicopters were hovering in the area.
They also said the US military has offered a reward of 20,000 dollars through a local radio station for any information leading to the soldiers' whereabouts or their safe release.
The US military has around 90,000 military personnel in Afghanistan, while 10,000 extra forces are expected to arrive in August. Around 50,000 troops from other NATO and non-NATO countries are also based in the war-torn country.
Taliban have held another US soldier, Bowe Bergdahl, for more than one year. Bergdahl was captured in eastern Afghanistan when he left his unit in June last year. The hostage has appeared in several Taliban videos, the last one released in April.