PANAMA CITY (AP) — A four-hour blackout has caused delayed and cancelled flights at Panama's main international airport.

Tocumen Airport says an internal electrical problem cut power to the airport Monday morning. Power went out about 6 a.m. local time at one of Latin America's busiest airports. It was restored later in the morning.

Panamanian airline COPA warned passengers its flights would be delayed significantly.

The airport is currently undergoing a $1 billion expansion.