Iranian media report a former deputy foreign minister and close ally of President Mahmoud Ahmadinejad has been arrested on financial corruption charges.
The reports say Mohammed Sharif Malekzadeh was taken into custody on Thursday.
Malekzadeh resigned this week, just three days after he was named deputy foreign minister.
The ex-deputy foreign minister quit as his boss, Foreign Minister Ali Akbar Salehi, was facing impeachment proceedings over his appointment in a growing political rift between hardliners and Ahmadinejad.
Malekzadeh had been facing corruption charges and lawmakers threatened to remove Salehi from office if he did not fire Malekzadeh.
Ahmadinejad for months has been feuding with hardliners and clerics over the direction of Iran's future.
In his resignation letter, Malekzadeh said he could no longer suffer "dastardly manipulations and plentiful injustices" from his opponents.
Some information for this report was provided by AP, AFP and Reuters.