Additional Superintendent of Police Akash Megharia said Tigga was found hanging with a 'gamchha' (traditional cotton towel) tied around her throat inside the cabin of the AlipurduarRailwayHospital, where she was admitted a few days ago.
Finding the cabin locked at around 4 pm, her son had knocked on the door but received no answer, he said. Later, when the door was broken open in the presence of police and railway officials, she was found hanging.
Tigga (37) was a jawan with the 969 Railway Engineer Regiment of the Territorial Army and posted as a points-man at Chalsa station in the district.
She was allegedly kidnapped after her duties in the evening of May 9. She was found blindfold and tied to a post near the railway tracks the next morning. Tigga, however, said she was not physically harmed by the kidnappers.
She was later hospitalised.
Jalpaiguri SP Amit P Javalgi had earlier said some papers were found in her bag after Tigga was rescued and investigation was on. However, he refused to divulge what those papers were.
Her family members alleged that she was murdered.
Tigga had joined the Railways in 2005 on compassionate ground after her husband died. She later remarried.
She took tests to join the Railway Engineer Regiment of the Territorial Army and earned the distinction in 2011 but had no idea of the feat till she achieved it, Tigga had said earlier.