Two bombs have exploded in the southern Iranian cities of Dezful and Abadan, according to Iranian reports.
Iran has been hit by a spate of bombings in recent months
In both cities, the devices were planted in the governor's offices, the official Irna news agency says. No serious injuries were reported.
The attacks are the latest in a series to hit the southern Khuzestan province, at the heart of Iran's oil industry.
Eight people died when bombs exploded by a government office and bank in the provincial capital Ahwaz a month ago.
There was no immediate claim of responsibility for the latest explosions, according to reports.
"Hopefully, those behind the bombings will soon be found and punished," Dezful Governor-general Hamid Ghanaati told Irna.
The oil-rich Khuzestan province, which is home to about two million ethnic Arabs, has been rocked by a wave of unrest in recent months.
Iran accused British army forces across the border in southern Iraq of co-operating with bombers who carried out January's attacks in Ahwaz. The UK Foreign Office rejected the allegation.
A little-known ethnic Arab separatist group said in a website statement that it was responsible for the blasts, in which eight people were killed and 46 hurt.
The Iranian government also blamed attacks in June and October last year on the UK, but British officials again denied involvement.
In November, protests erupted in Ahwaz after ethnic Arabs accused the authorities of discrimination.