Iran's semiofficial Mehr News Agency on Friday said simultaneous blasts have struck three pipelines near the city of Qom, cutting the flow of gas.
Mehr said the blasts, which occurred at 5:50 a.m. outside the town of Salafchegan, south of Teheran, were felt miles away.
Local official Majid Bojarzadeh said the blasts were not caused by technical failures, but did not elaborate if officials believed the explosions were acts of sabotage.
He said operations were under way to repair the pipelines and restore the gas flow.
Iran's oil and gas sector has been hit by an increasing number of attacks in recent months, but authorities have provided no explanations for the blasts.
Mehr did not say how much gas flows through the lines.