The man has duped over 10 Army personnel in last two years, police said.
A 35-year-old man was arrested for allegedly posing as an Army Major and cheating soldiers, police said on Friday.
The accused has been identified as Hemant Kumar, a resident of Partapur village in Hapur district of Uttar Pradesh, they said.
Kumar has duped over 10 Army personnel in last two years, police said.
He had himself served in the Army from 2001 to 2013. During his service period, he had served in 1st Medium Regiment of Artillery at Jodhpur, they said.
Due to his "bad habits", he went underground to evade arrest by Army Police and was declared "deserter" by his Army unit, police said.
They said Kumar used to rob and cheat Army personnel in trains coming home on leave after becoming friends with them by posing as a Major in the Army.
Since Kumar is ex-Army personnel, he utilised his knowledge of defense services to influence soldiers, police said.
"We received inputs from Military Intelligence that one person was involved in current spate of cheating and robberies with Army personnel on different railway stations of Delhi and NCR. He was arrested from near New Delhi Railway Station on Thursday" said Deputy Commissioner of Police (Special Cell) Pramod Singh Kushwaha.
Many documents related to various Army jawans including their identity cards, health cards, driving licenses, ATM cards were recovered from Kumar's possession, he said.
"During interrogation, the accused revealed that he started his criminal activities by making friendships with army personnel by posing as Major or Captain in the Army. After winning their faith, he cheated them or stole their belongings including their I cards. He also used to extort money from them for returning these cards and belongings," DCP Kushwaha said.
Kumar was earlier arrested in three such cases registered across the city, the DCP said.