Iranian authorities have arrested the kidnappers of an Irish and two German tourists, who were released on Sunday after a three-week ordeal, the foreign ministry said Thursday.
"These people are in the hands of the intelligence ministry, and it is up to that ministry to provide the necessary information," foreign ministry spokesman Hamid Reza Assefi said, without giving further details.
The trio were kidnapped around December 2 by bandits while cycling near Nosrat Abad, on the road between the ancient city of Bam, which was devastated by a killer earthquake Friday, and Zahedan.
Their kidnappers, originally believed to be drug smugglers disgruntled by the police seizure of a consignment, had demanded a five-million-euro (six-million-dollar) ransom.
But Intelligence Minister Ali Yunessi said the kidnappers were linked to al Qaeda.
"The hostage-takers claimed to be linked to al Qaeda," Yunessi said in a statement on Sunday, when the hostages were released.
And at a press conference after their release, the tourists said their abductors had claimed to be "Taleban linked to al Qaeda," but added that they had not been mistreated.
One said their captors spoke Farsi, so he assumed they were Iranians.
Iran had said it would not pay the ransom, and asked Germany and Ireland also to not give in to blackmail.
Last year, the German government came in for widespread criticism after it allegedly agreed to pay a ransom to free nine of its nationals seized by Islamic militants in Algeria.
The area in Iran where the kidnapping took place is near the border with Afghanistan and Pakistan, and is notorious as a corridor for the smuggling of heroin, opium and cannabis.
Iranian security forces maintain a strong presence there, with armed clashes between troops and traffickers often reported.
Tourists are urged to take extra care in the area, although like most embassies, Iran gives no specific instructions to foreigners travelling in the area besides urging them to exercise caution.