St. Louis, MO (AP) – An officer at St. Louis’ busiest airport fatally shot a man who wielded a knife early Friday morning outside the doors of a terminal, police said. No one else was injured.

The shooting at St. Louis Lambert International Airport happened around 1 a.m., St. Louis County Police spokesperson Vera Clay said.

The area is located near the light rail line that transports travelers to the terminal and isn’t behind a security checkpoint, according to maps of the airport posted on its website.

The rail line to Terminal 1 was closed for about three hours, with shuttles taking people from other drop-off points, but was reopened later Friday morning. The airport remained open, Rhonda Hamm-Niebruegge, the airport director, said in a statement.

Clay said officers had noticed the man, who was not identified, in an area where he should not have been and refused to leave.

Clay said the man showed officers a knife when they tried to get him to move. Officers used Tasers but the man continued to advance toward the officers and one of them fired their gun, fatally wounding the man, Clay said.

“We don’t believe this was an individual trying to catch an airplane or coming into town,” Clay said.