A man was taken into custody Wednesday following a bomb threat on a Greyhound bus that was headed from Milwaukee to Chicago on the inbound Kennedy Expressway, according to Illinois State Police.

Witnesses told investigators the 22-year-old Chicago man, a passenger, was walking through the aisles of the moving bus, “singing and threatening to blow up the bus,” police said in a statement.

Police received a call from the bus driver at 4:23 p.m., who said a person on board was causing a disturbance and had made a bomb threat. Responding officers pulled the bus over on I-90 southbound near Keeler Avenue, police said.

Officers entered the bus and approached the man, who actively resisted, police said. He was removed from the bus and taken into custody.

All passengers were removed from the bus, police said. No one was injured.

A bomb dog arrived on scene and conducted a sweep of the bus. No explosive devices were found, police said.

The man was taken to a hospital for evaluation, according to police. No charges had been filed as of Thursday afternoon and the case remained under investigation.

Greyhound did not immediately respond to requests for comment.