Four are dead and one is injured in Australia’s second deadliest mass shooting since the 1996 Port Arthur massacre in Tasmania.

A 45-year-old gunman began opening fire with a pump-action shot gun at a motel in the northern city of Darwin before opening fire at other nearby locations in the city’s central business district around 6 p.m. Monday. Pump-action shotguns are largely prohibited in the country under sweeping legislation passed in the aftermath of the Port Arthur shooting, where 35 people were killed.