From the UK Telegraph:
Traditionalist clerics in Iran are blocking the extradition of senior al-Qa’eda members, including one of Osama bin Laden’s sons, amid growing evidence that they are masterminding terrorism in other countries. Western and Arab intelligence sources quoted in The Washington Post said up to 400 al-Qa’eda terrorists were being sheltered in eastern Iran close to the Afghan border by an elite religious militia, the Jerusalem Force.