Several students were seen jumping from the commercial building in the western city of Surat after it caught fire. Most of the victims were teenage girls who were studying at a tuition center in the complex.
At least 19 students died and 20 others suffered serious injuries in the western Indian city of Surat after a commercial complex caught fire on Friday. Another youth died in hospital on Saturday.
More than 50 students were in classes when the fire erupted in the Takshashila Arcade complex, which housed a tuition center on the multistoried building's top floor. Sixteen of the dead were young women who had been preparing for exams at the center, which, according to government officials, had been illegally set up.
"The fire was caused by a short circuit in one of the air-conditioning ducts on the ground floor ... and spread to the third floor," said U. Upadhyay, Surat's fire and emergency services commissioner.
Officials said the fire spread through packed classrooms due to the building's inflammable roofing.
All of the dead were under 20 years of age, according to the Reuters news agency.
Authorities in the state of Gujarat, where the fire broke out, have ordered an inquiry into the incident.
State police said Saturday it had charged three owners of the Takshashila Arcade building with culpable homicide not amounting to murder, and attempted culpable homicide. Surat police commissioner Satish Sharma told reporters that one of the accused had been detained.
"The other accused will be arrested soon," he added.
The Takshashila Arcade was authorized to have just one floor, but the owners illegally added two more floors on top of the building, according to Basant Parekh, a chief fire official in Surat city.
Prime Minister Narendra Modi offered his condolences to the victims' families in a Twitter message, saying he was "extremely anguished by the fire tragedy in Surat."
"My thoughts are with bereaved families. May the injured recover quickly. Have asked the Gujarat Government and local authorities to provide all possible assistance to those affected," the premier said.
Deadly blazes in India are not uncommon. In February, at least 17 people were killed in a Delhi hotel fire.
shs/jlw (AFP, dpa)