HARLEM, Manhattan (PIX11) — A man who brought a gun onto the subway was taken into police custody early Tuesday morning after a group of MTA workers spotted the firearm and called the police, according to the NYPD.

The man was taken into custody at the 125th Street station in Harlem after police were called around 4:15 a.m. The MTA employees were on a northbound No. 4 train when they saw a passenger in the train car with a gun in his waistband, police said.

The workers notified the NYPD and the train was held at the 125th Street station until the police arrived. The suspect was taken into custody, but charges had not been released, as of 6:30 a.m. 

The MTA tweeted No. 4 trains were delayed. It wasn’t immediately clear if normal service had resumed.

“Northbound 4 trains are running with delays after NYPD responded to a person being disruptive on a train at 125 St,” NYC Transit tweeted.