There was no evidence linking the attack at the Resorts World Manila entertainment complex to fighting between government troops and Islamist militants in the country's south, said Ernesto Abella, a spokesman for President Rodrigo Duterte.

"All indications point to a criminal act by an apparently emotionally disturbed individual," Abella told a news conference. "Although the perpetrator gave warning shots, there apparently was no indication that he wanted to do harm or shoot anyone."

The gunman killed himself in his hotel room after being shot and wounded by resort security, police and Resorts World management said. A second "person of interest" who was in the casino at the time was cooperating with the investigation, police said.

Most of the dead suffocated in the chaos. Fire bureau spokesman Ian Manalo said many guests and staff had tried to hide from the gunfire rather than get out of the building when the attack began shortly after midnight (16:00 GMT) and fell victim to the choking smoke.

Oscar Albayalde, chief of the capital's police office, said those who died were in the casino's main gaming area.

"What caused their deaths is the thick smoke," he told reporters. "The room was carpeted and of course the tables, highly combustible."

A Resorts World Manila official said the dead included 22 guests.

REUTERS