He said experts from the Office of Forensic Science would inspect the scene this morning to determine the cause of the fire.
Firefighters took almost two hours to control the fire that broke out at the Grand Park Avenue Hotel, located in the prime business area of Sukhumvit at around 10pm last night.
One seriously injured foreign tourist, a Russian woman, has died; 21 others, including four Thais, were injured in the fire.
Pol Col Rattasak Raksalam of Thong Lor Police Station refused to identify the woman, saying she succumbed to her injuries at Kluinamtai Hospital 1 at about 4am.
Gen Anuchai said that according to the initial investigation, the fire began on the fourth floor in a function room zone that was closed at the time.
It was believed that an electrical short circuit may have been the cause of the fire, but experts are investigating.
The fourth floor function room area was totally burned.
Meanwhile, the Bangkok Metropolitan Administration (BMA) has announced the hotel as an offlimits zone, awaiting Public Works Department verification the safety of the structure and inspection of the fire sprinkler system to determine whether it worked properly during the fire.