Albayalde said the man was Jessie Carlos, 43, a Catholic with three children from Manila who had been banned from all casinos in April following a request from his family because of a gambling addiction.
"This incident was confined to the act of one man alone, as we have always said", he said at a press conference.
The Islamic State terrorist movement had claimed the attack on Resorts World Manila on Friday was carried out by a jihadist with the nom de guerre Abu al-Kheir of the Archipelago, suggesting he was from the Philippines.
Manila police chief Oscar Albayalde said the security footage of the suspect in the attack indicated a clear motive, as the gunman headed straight for a storage room in the back of the casino that contained poker chips. The shooting was initially assumed by some to be a terrorist attack, but it turns out the suspect was a Philippines Department of Financing employee who had a gambling problem at the casino. He forced his way into Room 510, where minutes later, police and hotel security found him inside the room, underneath covers he had set on fire, with the tip of his M4 rifle pointed towards his mouth.
The casino's CCTV showed the gunman firing shots at the ceiling and setting gaming tables ablaze. He's then seen in an elevator, dressed in black with a backpack, with two women behind him.
Fears about IS' involvement in the attack were also intensified when the Site Intelligence Group, a US-based organization monitoring extremists' Web sites, said a Filipino ISIS operative "identified the alleged attacker and noted that his main objective was to burn the casino inside". "He is only one", Albayalde said. Instead, 37 people died of smoke inhalation while hiding from the gunman.
Police authorities eventually determined the Resorts World Manila attack was caused by a single gunman with no known ties to terrorism.More news: Three days of mourning after Portugal wildfires kill more than 60
"We can't accept that my son became like this, he was a very kind son", she said.
Resorts World Manila has pledged compensate victims' families 20,000 dollars each, and released video showing how the terrifying attack unfolded.
'That is not the work of ISIS, ' Duterte told reporters, using an acronym for Islamic State. The attack on the complex killed over 30 people. On Friday, a gunman entered the complex and set fire to its casino, triggering a blaze that left at least 38 people dead. The lone gunman, Jesse Carlos, 42, who had been employed by the Finance Department, was carrying a large bag with him as he made his way into the Resorts World Manila casino and resort.
Albayalde said the assailant was probably a foreigner, describing him as a Caucasian who spoke English.
The NDRP is an online system of excluded persons developed by Pagcor, which is accessible to licensed casinos and major operators of electronic gaming.
The attack sent hundreds of people fleeing through the complex and into the night. He also said they do not know where the gun used came from.