A Manhattan man was arrested after cops allegedly found him carrying a bag full of weapons and ammunition on the R train yesterday, and reports indicate he was a former Marine with a history of mental illness.

According to the NYPD, 27-year-old Christopher Palumbo was arrested at around noon after cops responded to a call about a man carrying a firearm on a bus in Bay Ridge. When they arrived at the scene, authorities say that Palumbo, a Chelsea resident, had already exited the bus; cops canvassed the R train subway station in the vicinity of 86th Street and 4th Ave, and say they eventually found Palumbo in the subway station holding a duffel bag that had protruding weapons.

NBC News reports that Palumbo was allegedly carrying a shotgun, ammunition, a laser and a machete with him. His mother told the station her son was a Marine who served three tours in Iraq, and that he has a history of mental illness and blames himself in part for 9/11.

Palumbo has been charged with criminal possession of weapon, grand larceny and criminal possession of stolen property.