The identity of the victim, believed to be in his 40s, has not been established. The accused, identified as Mahendra Pal, in his early 30s, was found roaming on the bridge at around 10.30 am with a knife in hand.
After scaring people, mostly railway commuters using the bridge to get onto the platforms, he stabbed the victim who was caught unaware.
The victim appealed for help but nobody came forward.
By the time, cops reached the spot, it was too late as the victim was found in the pool of blood.
The accused had been arrested and an enquiry was going on, said cops.
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