The incident took place when the gunner, Dhirender, was standing outside his employer's house in Siyani Gate area when two unidentified men on a bike snatched his rifle and fled, police said.
Police have registered an FIR and manhunt has been launched to nab the accused, said a senior police officer.
Meanwhile, Sihani Gate police station in-charge Manoj Yadav was today suspended by Ghaziabad senior superintendent of police for allegedly not properly entertaining rape case of a Dalit woman, using abusive language and misbehaving with complainants.