36 BODIES FOUND IN MANILLA CASINO ENTERTAINMENT RESORT

At least 36 bodies have been found at the Resorts World Manila entertainment complex that was stormed by a gunman, in what officials believe was a botched robbery.

Most of the dead suffocated in the chaos as guests and staff tried to flee choking smoke at the complex after the attack began shortly after midnight.

Police office chief Oscar Albayalde said they were in the casino's main gaming area.

"What caused their deaths is the thick smoke," he said.

"The room was carpeted and of course the tables, highly combustible."

A resort official said the dead included 13 employees and 22 guests.

A South Korean person was among the dead, apparently after a heart attack, a foreign ministry official said.

Officials said at least 54 people were also injured, some seriously.

The gunman burst into the Manila entertainment complex , firing gunshots and setting a casino ablaze.

Videos posted on social media showed people fleeing as several loud bangs were heard.

At about dawn, the suspected gunman took his own life in a hotel room in the complex, which is close to Ninoy Aquino International Airport and an air force base, police said.

They said the gunman was tall with a pale complexion and spoke English.

But police later said they were looking for a second "person of interest", who is believed to be a Philippine national.

PHOTO: Guests and staff tried to flee choking smoke at the complex. (AP: Tikos Low)

Police 'looking into robbery angle'

US President Donald Trump said Washington was closely monitoring what he described as a "terrorist" attack unfolding in Manila.

But local police said the gunman's motive was likely robbery and the incident was not terror-related.

National police chief Ronald dela Rosa told DZMM radio the lone gunman had not aimed his assault rifle at people and may have been trying to steal casino chips.

"Don't panic, this is not a cause for alarm. We cannot attribute this to terrorism," he said.

"We are looking into a robbery angle, because he did not hurt any people and went straight to the casino chips storage room.

"He parked at the second floor and barged into the casino, shooting large TV screens and poured gasoline on a table setting it on fire."

The capital's police office spokeswoman Kimberly Molitas said 113 million Philippine pesos ($3 million) worth of casino chips stolen during the raid had been recovered.

Philippines President Rodrigo Duterte's spokesman said there was no evidence linking the attack to fighting between government troops and Islamist militants in the country's south.

"All indications point to a criminal act by an apparently emotionally disturbed individual," the spokesman said.

"Although the perpetrator gave warning shots, there apparently was no indication that he wanted to do harm or shoot anyone."

Resort owner Travellers International Hotel Group Inc said authorities were still seeking details.

"We have been informed of several casualties, the number and identities of whom have yet to be determined," it said in a statement.

Manila on high alert in fight against Islamist rebels.

The Philippines has been on heightened alert amid a crisis in the south of the country, where troops have been battling Islamist rebels since May 23.

President Rodrigo Duterte declared martial law on the southern island of Mindanao last week.

Police chief dela Rosa said it was possible militant group Islamic State would claim responsibility for the incident for propaganda purposes, and it did nearly 24 hours later.

It was quickly rejected by National Security Adviser Hermogenes Esperon.

"If the lone gunman was really an IS terrorist, why did he not shoot and kill people in the casino? He only went for the casino chips," he said.

Mr Duterte has said he fears Islamic State's "terrible ideology" will spread on Mindanao, an island of 22 million people, and has warned it could become a haven for supporters fleeing Iraq and Syria.