MUMBAI, Jan. 26 -- The assailant who stabbed a college teacher in a crowded local train at Malad station on Saturday evening was arrested early on Sunday. The arrest, which concluded a 12-hour manhunt, brought closure to a heartbroken family but left millions of commuters in Mumbai feeling nervous and vulnerable. Omkar Shinde, 27, a resident of Kurar village in Malad east, which is also where the man he killed, Alok Singh, 33, lived, was apprehended on his way to the railway station. He was to board a train to Grant Road, where he worked in a metal workshop. On Saturday evening, Shinde had fatally stabbed Singh, a teacher at NM College, while they were alighting from a local train at Malad station. The two had argued over right of way in the train compartment as the train approached Malad. As the train drew to a halt, Shinde stabbed Singh in the abdomen with forceps used to cut steel, which he had spirited away from his workplace, and then fled. As news of the murder spread, triggering horror among millions of the city's commuters, Government Railway Police (GRP) began to scour CCTV footage to track down Shinde. Only hours after the incident, a chilling video surfaced online, showing a panicked Shinde running on a Malad foot overbridge. CCTV footage showed Shinde boarding a train for Vasai, from where he boarded a train for Malad, where he reached at 8pm. Shinde, who not two hours earlier had stabbed a man to death, then spent time with friends but did not say anything about the stabbing. A police team arrived at Shinde's home in Malad east at 5.30am, when his brother and mother told the police he had left for work 10 minutes earlier. Police alerted the Railway Protection Force, after securing Shinde's mobile number from his brother. Shinde was arrested while he was approaching Malad station, where he was to board a train for work. "We arrested Shinde at 6am on Sunday, after he left his house," said Dattarey Khuperkar, senior police inspector, Borivali GRP. Shinde has been arrested under section 103 of the Bharatiya Nyaya Sanhita (BNS) for murder. He has been remanded to the GRP's custody until January 30 a by Borivali magistrate's court. While the trigger for the murder appears to be the dispute over alighting from the train, senior police officials say the sheer brutality of the attack-stabbing a stranger over a petty argument-suggests deeper issues. "We are investigating to see if there was prior enmity or if any other factor could have influenced such a violent outburst," said a police official. Singh's family, overcome with grief, alleged that there was a delay in getting Singh medical treatment, which could have been decisive. "It is shocking that the attacker stabbed Singh and fled on foot without anyone noticing. Where was the patrolling staff on the platform? We want the men to be suspended," said Singh's brother Mahesh. GRP officers said Shinde has confessed to arguing with Singh over right of way in the compartment as the train approached Malad station, said Kishore Shinde, assistant commissioner of police, GRP....