NAVI MUMBAI, May 13 -- A 20-year-old man from Uttar Pradesh has been arrested for allegedly posing as a working professional and swapping commuters' laptop bags with his own on Mumbai's suburban railway network. The accused, identified as Karan Rajeshwar Mishra, was arrested from his native village in Uttar Pradesh on May 7. Police said his arrest helped solve five laptop theft cases: four registered in March and one on April 11 at Vashi Railway Police Station. According to the police, Mishra would board suburban trains in formal attire, carrying a laptop bag filled with scrap material to avoid suspicion. He allegedly targeted working professionals travelling with laptop bags, especially during peak hours. "He would discreetly exchange the commuter's laptop bag with his own bag containing scrap material and get off the train before the victim realised the theft," said a police officer. A breakthrough came in the April case. "The stolen laptop bag had a distinctive design, which helped us trace him. He was later seen stopping for a snack and making a payment through UPI. We traced the transaction details." said the investigating offier. The trail led the police to a village in Uttar Pradesh and he was brought to Navi Mumbai on transit remand....