Police officers secure the surroundings of Resorts World Manila after an attack in Pasay City, the Philippines, on June 2, 2017. [Photo/Xinhua]

MANILA - Unidentified gunmen attacked Resorts World Manila in Pasay City around early hours of Friday, causing injuries among the hotel and casino guests who scampered after the shooting.

Witnesses said they saw masked gunmen attacked the hotel. Gunman reportedly broke into the casino of the hotel. Parts of the hotel is on fire.

Resorts World Manila is an integrated resort located in Newport City opposite the Ninoy Aquino International Airport Terminal 3 in Pasay City.

Witnesses said they heard somebody shouted "IS." There were reportedly two masked men armed with long guns.

The Resorts World issued a statement after the shooting saying the hotel is "currently on lockdown following reports of gunfire from unidentified men."

"The company is working closely with the Philippine National Police to ensure that all guests and employees are safe," the statement read.

No group has claimed responsibility for the attack.

Some witnesses said they heard gunshots, so they hid in the bathroom.

Resorts World Manila chief operating officer Stephen James Reilly told reporters he could not confirm how many casualties in the building.

"I can confirm that shots were fired. I cannot confirm how many gunmen are in the building," Reilly said.

He added, "We do not know the purpose at this time."

There is no official statement yet from the police.

Some of the hotel guests were foreign nationals, including South Koreans and Japanese.

TV footage showed people running out of the building after the attack.