The Fort Dodge Police Department says a local robbery suspect is currently on the loose. Chief Tim Carmody says 27 year-old Nathaniel Lee Altman remains at large after an alleged robbery at the downtown Sinclair convenience store on Sunday night. Shortly before 11:00pm, Altman allegedly threatened two employees with a knife and demanded money. He received an undisclosed amount of money and fled the scene. Altman is being sought on one 1st degree robbery and two 1st degree theft warrants. Anyone with information is encouraged to contact Fort Dodge police or Webster County Crime Stoppers.