A suspected militant from Germany has been detained in north-west Pakistan wearing a burka, police say.
They told the BBC the man was in a vehicle with two other men and a young girl when they were stopped at a check-point in Bannu district.
The German was travelling with a fake Pakistani passport, officials say.
Meanwhile the Taliban has offered to swap 33 soldiers captured on the Afghan border if a number of militants are in return released from Pakistani jails.
They have warned the soldiers may be harmed if the government refuses.
Shafqat Khan, a senior police officer in Bannu, told the Reuters news agency the arrested German and his accomplices were pretending to be a tribal family.
The German embassy in the Pakistani capital Islamabad has yet to comment on the arrest.
A policeman at the checkpoint where the arrest took place said that the burka worn by the German covered his face and body.
The arrested German could have links with militants in the lawless north-western region, police say.
Police in Bannu told the BBC the suspect and his two accomplices were in a car travelling from the town of Mirali to Peshawar.
They said they were taken by the intelligence services for interrogation.
The area where he was arrested - near the border with North Waziristan - is a known stronghold for al-Qaeda and Taliban.
The BBC's M Ilyas Khan in Islamabad said foreigners including Western nationals and Arabs have been arrested in the past for illegally travelling in the area.
The US has urged Pakistan to launch a military offensive in North Waziristan, but the Pakistani army says it lacks the resources to do so.
Last week an American man who said he was on a mission to hunt down Osama Bin Laden was arrested in the Chitral area carrying a pistol, dagger, sword and night vision equipment.
In a separate development, Pakistani officials say that about 40 out of more than 60 soldiers who went missing when the Taliban attacked a border checkpoint on the night of 13 June are still unaccounted for.
About 14 of them were taken into custody by the Afghan forces in the Afghan province of Kunar and were handed over to the Pakistani mission in Jalalabad.
A Taliban spokesman in Mohmand tribal region, Yasin Safi, told the BBC Urdu service that they would release the soldiers if an unspecified number of Taliban members were released in exchange.
Last week the Taliban said that most of the men were being held in Afghanistan after they fled across the border following the attack.
Correspondents say it not surprising if they are now in Pakistan, because it is well known that the Taliban's military network straddles the Afghan-Pakistan border.