At least 36 people have been killed and 50 injured after an overnight passenger train derailed in southern India, according to railway officials, in the latest accident to hit the country's gigantic, but poorly maintained, rail network.

Seven coaches of the Hirakhand Express were thrown off the tracks late on Saturday, with some landing on a goods train that was on a parallel track, Chandralekha Mukherji, divisional railway manager, told the Associated Press news agency.

Rescue workers were trying to cut open the mangled coaches on Sunday morning near the Kuneru railway station, in the Vizianagaram district of Andhra Pradesh state. The train was travelling between Jagdalpur, in Chhattisgarh state, and Bhuvanesawar, in Orissa.

"Thirty-six people have been killed so far and 19 bodies have been identified," said JP Mishra, a spokesman for East Coast Railway, adding that the toll could rise further as many people were still trapped.

Officials were investigating whether Maoist rebels had tampered with the track, after eight coaches and the engine of the Jagdalpur-Bhubaneswar express were derailed at around 11:00 pm (1730 GMT) on Saturday.

Anil Kumar Saxena, a national railway spokesman, said investigators were considering possible sabotage of the tracks by Maoist rebels, who he said were active in the area.



"It is being looked into, it is one of the many angles we are looking into," he told AFP.

"There is some suspicion [of sabotage] because two other trains had crossed over smoothly using the same tracks earlier in the night."

Police in Odisha, where the train was headed, dismissed any involvement by Maoist rebels, known as Naxals, in the derailment.

"We totally reject any possibility of Maoist involvement in the derailment. Kuneru is not a Naxal-hit area," an unidentified senior intelligence officer was quoted as saying by the Press Trust of India.

Poor safety record

India's railway system is the world's third-largest but is severely hampered by a lack of modern signalling and communication systems, as well as poor maintenance of tracks and equipment. Manual signalling is still used at several places, raising the risk of human error.

In November, 146 people were killed when a packed passenger train derailed near the town of Kanpur, in Uttar Pradesh, in the deadliest rail accident in the country in at least five years.

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According to a government report in 2012, about 15,000 people are killed each year in train accidents. The worst occurred in 1981, when a train fell into the Bagmati River in northern India, killing nearly 800 people.

Narendra Modi, India's prime minister, pledged last year to invest $137bn over the next five years to modernise the railway network, which is used by about 23 million passengers a day.

In a message on Twitter on Sunday, Modi expressed his condolences for those killed in the latest accident and said that the railway ministry was monitoring the situation closely.