At least 32 people were killed and 50 were injured when a passenger train derailed in India's southern state of Andhra Pradesh, officials said Sunday. The accident took place late Saturday night when the locomotive and seven coaches of the Hirakhand Express derailed near the Kuneru station in Vizianagaram district. The train had a total of 22 coaches. "Many passengers were killed on the spot as the coaches got badly damaged in the derailment," regional railways spokesman JP Mishra told dpa. "A few more died on the way or in hospitals." Mishra said that 50 people had been hospitalised, but the death toll could rise as some passengers are in a serious condition. The train was travelling between Jagdalpur in central India to Bhubaneshwar in the east, at the time of the accident. Rescue teams worked overnight to save people trapped in the train carriages and remove the bodies. Blow-torches were used to get the passengers out of the mangled coaches. "The reasons for the accident are as yet unclear," Mishra said, adding that railway authorities have already ordered a probe to determine the exact cause of the accident. Brake failure or negligence on the part of the train driver could have caused the accident, but sabotage had also not been ruled out. "Left-wing Maoist rebels are active in the region where the accident occured. We will look into the possibility if rail tracks had been tinkered with," a railways official said on condition of anonymity. Prime Minister Narendra Modi expressed his condolences after hearing of the accident. India's railways carry an estimated 20 million passengers daily and have a poor safety record. According to the National Crime Records Bureau, over 25,000 people have been killed in rail accidents each year since 2010. In November, 149 people were killed when a passenger train derailed in northern India, the deadliest train accident in the country in the past five years.