Twin blasts ripped through two coaches of a passenger train Thursday morning minutes after it pulled into the station, killing a 22-year-old woman and injuring nine people, officials said.
Authorities suspect the blasts were caused by bombs planted on the Bangalore-Guwahati Express train, said M. Bhupati, the spokesman for India's southern railway system.
"The police are already on the job, they are investigating what kind of bomb it was and what was the purpose," Chennai Central station General Manager R.K. Mishra told reporters.
The blasts come amid heightened security nationwide for India's massive general election, which is held in phases over several weeks.
At least one of the blasts erupted from underneath a seat where the 22-year-old victim was sitting, killing her, Mishra said.
Two of the nine injured were hospitalized for serious injuries, while police investigated and bomb squads checked the train for more explosive devices, Mishra said.
There was no immediate claim of responsibility for the blast in a region of India considered relatively peaceful.
The train originated in Bangalore and was headed to Gauhati, the main city in the remote northeastern state of Assam. The train was running behind schedule, so officials were not sure if the target was Chennai city, the capital of Tamil Nadu state.