It said police, fire trucks and a SWAT team were in the area.
Gun shots and explosions rang out in an entertainment resort in the Philippine capital Manila early on Friday as local media reported armed men were inside the complex.
Resorts World Manila said on social media it was in lockdown and police were in control of the situation.
"We ask for your prayers during these difficult times," Resorts World said on Twitter.
Witnesses who spoke to radio stations said several gunmen were seen in the complex. News channel ANC said there were two gunmen, wearing masks and black clothes.
Pictures circulated on social media of the resort, close to the city's airport, of plumes of smoke pouring out of a building.
A source at one of the resorts told Reuters employees were being evacuated and declined to give more details.
The Philippines has been grappling with incidents of terrorism, especially on the southern island of Mindanao.