Iran's state media says its security forces have arrested the leader of an armed Sunni opposition group that is waging a violent low-level campaign in southeastern Iran.
The official IRNA news agency said that Iranian security forces had arrested Abdulmalik Rigi, leader of the Jundullah (Soldiers of God) group, while travelling to an "Arab country".
"Rigi was arrested in Persian Gulf waters while he was travelling on a plane via Pakistan to an Arab country," Mohammad Dehghan was quoted by the news agency as saying.
Jundullah has in recent years claimed responsibility for several bombing attacks inside Iran that have left dozens of people dead.
Alireza Ronaghi, Al Jazeera's correspondent in Tehran, said Rigi was a key target for Iranian intelligence.
"Iran's interior minster says it has been very important for Iranian intelligence agents to arrest him alive."
"Abdulmalik Rigi was in an American military base 24 hours before his arrest ... He also travelled to some European countries ahead of his arrest," Moslehi was reported by Iran's Press TV as saying.
Moslehi was also quoted as saying that the Americans had issued Rigi with "an Afghan passport and an identification card for travelling to Pakistan" and that Rigi was in league with British and Israeli intelligence.
The "Arab country" Rigi was reportedly travelling to is thought to have been Dubai.
The US, Britain and Pakistan all deny backing Jundullah, which operates in Iran's southeastern province of Sistan-Baluchistan, bordering Pakistan and Afghanistan.
The group, which Iran suspects of having links with the al-Qaeda network, gained prominence six years ago with a series of sporadic attacks and kidnappings.
It claimed responsibility for the bombings last October that killed more than 40 Iranians, including 15 from the elite Revolutionary Guards.
Jundullah accuses the government of discrimination against Sunnis and says that the minority Sunni tribes in southeastern Iran suffer at the hands of Tehran's Shia leadership, an allegation Tehran rejects.
Sectarian violence is relatively rare in Iran, but attacks and clashes have increased between security forces, Sunni rebels and drug traffickers in the country's southeast.