Afghanistan's security forces have captured a German man during a recent raid on a suspected Taliban bomb-making compound in the southern province of Helmand, Afghan officials say.

It appears to be a rare example of a European citizen fighting on the side of the insurgency in Afghanistan.

Omar Zwak, the provincial governor's spokesman, said on February 28 that the man was carrying documents identifying him as a German citizen.

He said the man was taken on February 26 along with two other suspected insurgents to a compound in Gereshk district.

The initial investigation suggested that he was not a prisoner of the insurgents and had been participating in making roadside bombs, Zwak said.

Gereshk police chief Ismail Khplwak said the man was a "military adviser of Mullah Nasir," commander of the commando-style Taliban Red Unit in Helmand.

The Afghan military showed photographs of a man in his 40s with a reddish-brown beard and wearing a black turban and traditional Afghan clothes.

An army statement said the man, who calls himself Abdul Wadood, was detained with other suspects in a joint operation by Afghan special forces and the country's air force.

Germany's authorities have not immediately commented.

But the German daily Die Welt reported that the man was a convert to Islam called "Thomas K" from Rhineland-Palatinate, near Frankfurt. The report said he had traveled to Afghanistan in 2013 to join the Taliban.

The Taliban, fighting to drive foreign forces out of Afghanistan and reimpose their vision of strict Islamic law, has not attracted thousands of foreign fighters from Europe like the Islamic State militant group once did in Syria and Iraq.

Fighters from neighboring countries such as Pakistan and Uzbekistan have been found battling alongside the Afghan Taliban. But U.S. commanders have said no significant numbers of militants from outside the region have been identified.

On February 24, General John Nicholson, the top U.S. commander in Afghanistan, told journalists that no more than a "smattering" of other foreigners have been seen with the local affiliate of Islamic State.

"A very small number. This is no comparison to what we saw in Iraq and Syria," he said.

With reporting by AFP, dpa, AP, and Reuters