Witnesses say an explosion was heard outside of a train station in New Jersey Monday morning, after a suspicious object was discovered in a nearby trash can.

Police say two men had called to notify them regarding a suspicious package that had been placed in a trash can just outside of the train station, saying that a pipe and wires were conspicuously sticking out of the bag.

FBI and local authorities had sealed off the area when an explosion was heard. It is unclear if the explosion was controlled, with conflicting reports from the City of Elizabeth.

A spokesperson for Mayor Christian Bollwage claimed the blast was controlled, but Mayor Bollwage later contradicted this claim, saying the explosive pack had detonated on its own.

He added that a major catastrophe had been averted, and that given the size of the explosive device, it could have “certainly killed or injured many.”

The incident comes after a weekend of bombings in New York and New Jersey. On Saturday night, an explosive device wounded 29 in Manhattan. In New Jersey, a pipe bomb exploded, and a stash of additional bombs discovered.

While no arrests have been made, the FBI has detained five individuals for questioning in connection to the bombings.