MUMBAI: Cameras equipped with facial recognition tech have helped Government Railway Police track down the suspected killer of a city college teacher in around 12 hours after the murder. The victim, Alok Kumar Singh (33), was stabbed to death after a fight on a local train at Malad station on Saturday evening.The 27-year-old suspect, Omkar Shinde, told police that he lost his cool after a tiff with Singh over alighting at the station. Shinde, who is into imitation jewellery and metal polishing, is believed to have used a small pair of tongs to stab Singh. He threw away the weapon while fleeing. Police are looking for it.Singh and his colleague S K Trivedi were heading home in a Borivli-bound slow local when the former was stabbed at the door of the coach. “We may have scanned footage from close to 200 cameras in the span of a night,” a Borivli GRP officer said. The GRP worked with Railway Protection Force and city police to track down the suspect.Explaining the sequence of events after the stabbing of the junior college teacher, police said Shinde ran on platform no. 1 and climbed a foot overbridge. Cameras captured him exiting the railway premises towards Malad (E) a minute later.“We wanted to check if the suspect was a frequent railway commuter and started looking through surveillance footage from five days before the incident,” a GRP officer said. Around 5-6 teams were formed. Logs were maintained for dates and timings that Shinde was captured on cameras, equipped with facial recognition tech, entering or exiting railway premises.“Shinde would typically board the 7.18am Up local from Malad and after work, he took board the 4.16pm local from Charni Road to head home,” said another officer. Surveillance footage from outside Malad railway station showed that Shinde preferred walking home in the evening. But in the morning, he would take an auto to reach the station.After studying these patterns, investigators set up a trap at the auto stand outside Malad station around 7am on Sunday. “We were not too sure if he would go to work as it was a Sunday. But we saw him getting off an auto,” said an officer. The team pounced on Shinde and brought him to the Borivli GRP chowky. He initially claimed he wasn’t aware of Singh’s death. Shinde resides at Kurar village in Malad with his parents and a brother. He works at his father’s metal polishing unit in Khetwadi, besides doing some imitation jewellery work on his own. Police said his father is a heart patient and has stopped working.On Sunday, Shinde was produced before a holiday court at Borivli which sent him to police custody till Jan 29. Police said he does not have a prior criminal record.