The fire was believed to have been caused by a student's candle that toppled over in the girls' dormitory at the Motufoua Secondary School. The dorm was an old wooden building whose door had been fastened shut and whose open windows were covered in wire mesh.
The girls, ranging between 14 and 17 years old, were locked inside their rooms when the fire broke out, Radio Tuvalu reporter Diana Semi told Australia's National Nine News.
"The girls were in the dormitory trying to escape from the fire but could not because all the doors were locked," Semi said Friday.
Government officials told the Australian Broadcasting Corp. Radio that 19 people had died. They said another 18 girls managed to escape the inferno by smashing down a door.
The girls' dormitory supervisor was killed as she attempted to battle past the flames to free the girls, Semi said.
The government said Friday it was launching an investigation into the blaze.
Motufoua is the nation's largest high school with about 300 students, both boys and girls.
Tuvalu Prime Minister Ionatana Ionatana revealed the tragedy to the country earlier Friday in an address on Radio Tuvalu. He planned to visit the school later Friday. Ionatana was also expected to attend a mass funeral for the victims.
A spokesman for the prime minister's office said the mass burial was decided on because the bodies were burned beyond recognition.
Tuvalu is one of the world's smallest nations in both population and size. Its 9,000 people live on 10 square miles of coral atolls in the Pacific Ocean, about 620 miles north of Fiji.
Formerly called the Ellice Islands, Tuvalu was ruled by Britain from the 1890s until 1978 when it became independent.
By Robert Keith-Reid
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