Manila, May 1 : A power outage at the Ninoy Aquino International Airport in Manila on Monday resulted in the cancellation of several domestic flights, Filipino authorities said. The Manila International Airport Authority (MIAA) said the power outage at Terminal 3 struck shortly after 1 a.m., reports Xinhua news agency. "Standby power is now supplying electricity to critical facilities enabling computer systems of airlines and immigration to function partially and enable processing of both inbound and outbound passengers," the MIAA said in a statement. "As a result, delayed flights shall be expected," it added. The MIAA said that operations personnel are now continuing to do the rounds of Terminal 3 to assist passengers. Transportation Secretary Jaime Bautista said the Terminal 3 generator system is used to supply power while the MIAA engineering team is looking into the cause of the power failure. Bautista said the outage caused slight congestion at check-in counters inside the terminal. President Ferdinand Marcos, now on an official visit to the US, has instructed Bautista to restore power "as soon as possible". A power outage also hit the Manila airport in January, triggering a technical glitch that delayed and caused cancellations of domestic and international flights. /IANS