The man responsible for the deadly Manila casino attack was a heavily-indebted Filipino hooked on gambling, police have said.
Police chief Oscar Albayalde said his family confirmed he was Jesse Carlos, a former Finance Department worker.
The family said he was more than £62,000 in debt "due to being hooked in casino gambling", according to Mr Albayalde.
The police chief said the family's account corroborated the belief that "this is not an act of terrorism".
Security footage shows Carlos casually leaving a taxi and walking calmly into a vast entertainment and gambling complex like any other visitor, before carrying out one of the Philippine capital's deadliest attacks in years.
Shortly afterwards, he dons a black ski mask, slips on an ammunition vest and pulls an M4 carbine assault rifle out of his backpack at the Resorts World Manila complex.
What followed borders on the surreal: a slow-motion arson attack and robbery so methodical and unhurried, with Carlos appearing to walk much of the way, even as he exchanges fire with a security guard and flees up a stairwell.
At least 37 patrons and employees died, mostly from smoke inhalation as they tried to hide on the second floor, including one the casino's VIP rooms.
Carlos fled to an adjoining hotel and reportedly killed himself.
The Islamic State militant group claimed responsibility for the rampage early on Friday, but video footage bolstered the government's case that it was a botched robbery by a lone attacker with no known link to terrorism.
Philippine president Rodrigo Duterte said the attacker was simply "crazy".
He questioned what he was going to do with the £1.5 million haul of poker chips he had tried to take away.
Although Carlos was well armed - Mr Albayalde said he was carrying 90 bullets in three rifle clips - there are no confirmed reports that he shot any civilians.
Instead, he fired into the ceilings, scattering panicked crowds, some of whom jumped out windows to escape what they believed to be a terror attack.
Mr Albayalde said the security footage contained a clear motive: Carlos headed straight for a storage room that contained poker chips.
He is seen shooting through several thick white doors, breaking down one of them at 12.18am on Friday, only 11 minutes after his arrival.
Mr Abayalde suggested he started fires as a diversionary tactic and his next move was to try to escape.
More than 12,000 people were in the complex at the time; most were successfully evacuated.
"He could have shot everybody there," Mr Albayalde said.
"He could have killed hundreds of people inside that establishment. But he did not shoot anybody ... he just burned the casino."
The taxi driver who dropped off Carlos told police his passenger spoke fluent Tagalog and appeared normal during the ride.
The gunman asked him just one thing - to change the radio channel to the news instead of music, Mr Albayalde said.
"All indications ... point to a criminal act by an apparently emotionally disturbed individual," said presidential spokesman Ernesto Abella.
The Philippines has faced Muslim uprisings for decades, though much of the violence has occurred in the troubled south.
Many in Manila feared Friday's attack was linked to ongoing battles with militants aligned with IS in the southern Philippine city of Marawi.
The fighting has placed the country on edge and prompted Mr Duterte to declare martial law across the south.