A speeding bus exploded in a ball of flames after crashing into the central reservation on a southern Indian highway, killing 44 passengers as they slept.
Only five people on the vehicle escaped the inferno, including the driver and the cleaner who broke windows and fled before the fuel tank exploded, police said.
"The number of dead, which includes children, is 44," said local police spokesman Venkateshwarlu, who uses only one name.
Fatalities were high even by deadly Indian standards where bus crashes, particularly on the treacherous roads of the northern Himalayas, are common.
Venkateshwarlu said the driver and cleaner had tried to flee the scene of the accident, which occurred about 5am (1030 AEDT) on Wednesday between Bangalore and Hyderabad.
"The police caught them and they are now in our custody for questioning," he said.
Relatives of the victims screamed and broke down in tears outside the office of the bus operator in Hyderabad, 140 kilometres from the crash site.
Police arrived later to question the owners of Jabbar Travels, which offer buses to cities across the south of India.
Many of the victims were charred beyond recognition.
Television pictures showed flames leaping out of the vehicle, which was completely gutted by the time firefighters arrived.
The survivors were being treated in a nearby hospital in Wanaparthy, Venkateshwarlu said.
The Times of India reported that at least five of the victims were software engineers who were travelling home to celebrate Diwali, the Hindu festival, this Sunday.
Both Hyderabad and Bangalore are centres of India's booming IT industry, while Diwali is one of India's biggest festivals which sees tens of millions of migrants head back to their families.
"The main reason why the mishap occurred was because the bus was speeding and it hit against a road divider," district official Girija Shankar told the newspaper.
Around 140,000 people died in road accidents in India in 2012, according to the government's National Crime Records Bureau, which works out at 16 an hour.
Bad roads, speeding vehicles and poor driving are among the contributing factors.
