MANILA, Philippines (AP) — Nearly 300 domestic and international flights at the Manila airport in the Philippines were either delayed, canceled or diverted Sunday, causing misery for over 65,000 passengers during the New Year holiday after a power outage hampered air traffic operations.

Transportation Secretary Jaime J. Bautista in an evening news conference apologized for the inconvenience and said authorities are working to assist all affected passengers.

Bautista said the problem started in the morning, when the Air Traffic Management Center, which oversees all flights in Philippine airspace, lost communication, radio, radar, and internet because of the power outage.

The air traffic system was restored in late afternoon and flights resumed at Ninoy Aquino International Airport in Manila.

Officials said they requested airlines to mount more flights and to upgrade to more wide-body planes to accommodate more passengers, and that full recovery is expected after 72 hours.

Some travelers were outraged, among them tycoon Manny Pangilinan, chairman of the telecommunication company PLDT, who said he was on his way to Manila from Tokyo when the outage happened.

“We’re told radar and navigation facilities at NAIA down. I was on my way home fm Tokyo - 3 hours into the flight, but had to return to Haneda. 6 hours of useless flying but inconvenience to travelers and losses to tourism and business are horrendous,” he tweeted.