JAKARTA, July 21 — A blackout that left parts of Indonesia’s capital Jakarta and the country’s biggest airport without power today was caused by an explosion at a substation, an official from the state utility firm said.

Power shortages are common in Indonesia, where poorly maintained electricity infrastructure is one of the factors restricting growth in Southeast Asia’s largest economy.

Jemjem Kurnaen, an official from state power firm Perusahaan Listrik Negara (PLN), said it was not clear what had caused a transformer in the North Jakarta district of Muara Karang to stop working.

“There was an explosion there. It was not the transformer but the connecting equipment,” he said. “We’re investigating the cause.”

Mardawa, corporate secretary for PLN, said the problem had been isolated.

“Parts of the district are blacked out at the moment but gradually it is coming back again. We are investigating the cause,” he told Reuters.

The blackout hit Jakarta’s central business district, where many office buildings are located.

Andang Santoso, a spokesman for Soekarno-Hatta airport, said the airport had also been affected.

“Power is dead here, however we are using a generator so operations have not been disrupted. Check-in is still operating smoothly,” he told El-Shinta news radio station.

PLN in July raised electricity prices by an average of 10 per cent in an effort to boost revenue for new infrastructure.

However, analysts have said the increase is not enough to cover PLN’s costs and build infrastructure needed to shore up electricity supplies. — Reuters