Cairo: Egyptian Electricity Ministry Mohammad Shaker returned home on Sunday, cutting short a trip to Saudi Arabia, a day after an unprecedented disruption in TV broadcasting that officials said was caused by a power outage.

Shaker was asked by Prime Minister Ebrahim Mehleb to cut short his trip to the kingdom shortly after his arrival there, local media said. The minister and his aides were working on a report about the electricity cut that hit the TV building in central Cairo on Saturday.

Shaker was originally due to attend in the Saudi capital Riyadh scheduled talks on electricity cooperation between the two countries. His visit was to last five days.

The prime minister late on Saturday made an official apology for the disruption, which ran for about 30 minutes in the transmission of the main TV station and other official broadcasters.

Mehleb vowed an investigation into the incident, the first of its kind since Egyptian state television hit the airwaves in 1960.

“This incident will not be tolerated. There will be punishment,” Mehleb said in a phone-in to the official broadcaster. “When a power outage hits the TV building, this is an issue of national security.”

He said that a high-level committee will be set up to investigate the incident.

TV officials blamed a technical problem for the sudden power cut.

Essam Al Amir, the head of the state-run Radio and TV Union, ruled out that the outage had been caused by a criminal act. “The problem was due to a purely technical failure.”

Last month, a coordinated attack by suspected Islamist militants on power pylons, feeding Egypt’s media city, sent satellite TV stations off air.

In recent months, Egypt has experienced a rise in roadside bombs and attacks on electricity pylons, which authorities have blamed on extremists backing the deposed president Mohammad Mursi.

In 2013, the army toppled Mursi of the Muslim Brotherhood following enormous street protests against his year-long rule. Egypt has in recent years been hit by an acute energy crisis.