TEHRAN, Iran—Iran's official news agency says authorities have arrested suspects on charges of planting bombs and sabotaging energy facilities. It says they were tied to Arab and Western intelligence agencies.

The IRNA news agency said Friday they were "terrorists connected to foreign intelligence services" who planted bombs in Iran's southwestern Khuzestan Province, the heart of Iran's oil industry.

IRNA said Iranian security confiscated bombs and other weapons sent from a neighboring Arab country. It did not name the country or say how many people were detained.

Iran periodically announces the capture of alleged U.S. or Israeli spies, and often no further information is released.

Iran's oil and gas sector has been hit by an increasing number of attacks in recent years, prompting speculation that saboteurs may be responsible.