By Athit Perawongmetha
WIANG PA PAO, Thailand (Reuters) - A 10-year-old Thai girl called out for her mother and father as a blaze swept through her school dormitory "until her voice was gone", her mother said on Tuesday.
The fire broke out late on Sunday as the girls, aged between five and 12, slept at a Christian school for children of hill-tribe families in the northern province of Chiang Rai.
Investigators are looking at the possibility of faulty lighting on the ground floor below the dormitory.
Malawian Saw-wa's daughter, May, died in hospital. Her elder daughter survived by jumping from a second-floor window, she said.
"My eldest daughter said she heard May calling for mum and dad to help until her voice was gone," Malawian said.
"Never in my lifetime will I let my daughter out of my sight. The school must be held responsible for this. My daughter was my heart and soul."
Five of the victims have been identified and police were seeking to identify the others through DNA tests.
Police questioned witnesses on Tuesday, and said they had not yet reached a conclusion on the cause of the fire.
"We still need to gather evidence from the scene first on what caused this and whether this was due to negligence," said district police chief Prayad Singsin.
A forensics officer told Reuters evidence pointed to a loose light bulb melting on the ground floor of the two-storey building, causing the fire that killed the girls in the dormitory above.
Around 10 of the 19 girls that survived slept on the school grounds on Monday night as their parents had yet to arrive from far-flung areas to pick them up, said Tuenjai Tanachaikant a local who volunteered to help at the school after the fire.
Some of the parents also slept at the school where they lit incense sticks and prayed.
Prime Minister Prayuth Chan-ocha sent his condolences to the families of the victims and the school.
"The prime minister wanted to sent a message to all the teachers and students that the fire may burn down the school buildings but don't let it burn away their hopes," government spokesman Sansern Kaewkamnerd told reporters.
Prayuth said he had ordered government agencies to work to reduce the number of deadly accidents in Thailand. In Bangkok on Tuesday, a blaze at a restaurant and bar killed two people, police said.
(Additional reporting by Pairat Temphairojana, Panarat Thepgumpanat and Pracha Hariraksapitak BANGKOK; Writing by Simon Webb; Editing by Nick Macfie)