Philippine authorities said on Saturday they have yet to identify the gunman who attacked a casino complex in the capital, killing 37 people in a fire, but rejected claims he was a terrorist aligned with the Daesh.

Witnesses and investigators described the suspect that stormed the casino at Resorts World Manila on Friday as tall, Caucasian-looking, speaking English and with the build of a soldier.

In an online statement, the Daesh terror group said the attack was carried out by a suicide assailant with the Daesh nom de guerre Abu al-Kheir of the Archipelago, suggesting he was from the Philippines.

"They may claim credit, but according to our evidence, it is not so," presidential spokesman Ernesto Abella said in a statement given on radio.

"There is no truth that the incident was a terror act," he added.

"According to our evidence, the incident is a local peace and order concern."

The gunman barged into the Resorts World casino just after midnight on Friday, opening fire with an M4 rifle and torching gaming tables and carpets.

The victims died of suffocation due to the thick smoke from the fire, police said.

The suspect was later found dead in a room in a hotel adjacent to the casino building, burned beyond recognition and with a gunshot to the head.