The incident took place on Wednesday at Muttambalam in Kottayam.
Railway officials said the woman, Laila Thankachan, 47, was crossing the track when she was hit by the Parasuram express around 3.30 pm.
The railway gatekeeper, who was in his cabin, waved the red flag to alert the engine driver as the woman fainted and fell on the track, but in vain and the train stopped only after hitting her.
The gatekeeper said the two youths, who were near the woman, instead of helping her, were keen on capturing the impending ghastly tragedy on their mobiles.
However, in another incident on Wednesday, a 64-year-old man sacrificed his life while trying to save his hearing-impaired neighbour from an approaching train at Kozhikode.
Abdurehman, who was returning from the mosque, noticed the 70-year-old Raman walking on the railway track and saw a train approaching. He rushed to pull him away from the track but both of them were hit and killed on the spot.
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