CHICAGO — A 62-year-old bicyclist is in critical condition after he was attacked with a construction sign in the South Loop.

The attack happened around 1 a.m. Monday in the 2200 block of South State Street.

According to police, a witness said the 62-year-old man was riding a bicycle on the sidewalk when another man began hitting him with a construction sign and then with his own bicycle.

The 62-year-old was transported to Northwestern Memorial Hospital and is listed in critical condition.

No one is in custody. Area Three detectives are investigating.