Customers, staff robbed at gunpoint inside River North diner

Customers and staff were robbed at gunpoint inside a River North diner early Thursday morning. 

Chicago police said three men entered a business in the 300 block of W. Chicago Ave., Griddle 24, with guns and demanded money around 3:15 a.m.

Police said the group took money from the cash registers and then targeted personal property from four people in the diner. The armed men also hit a 23-year-old man in the head during the incident. 

The man was taken to Northwestern Hospital in good condition.

Sources told CBS News Chicago the 23-year-old victim was an employee, and the other victims were customers of the diner. 

No arrests have been made. 

Police are investigating.