Storm Lake, IA (KICD)– Additional charges have been filed in a Storm Lake stabbing investigation that began last week.

Police originally charged two 15-year-olds and a 17-year-old with participating in a riot last Tuesday after another teenager showed up at a local hospital with a stab wound. One of those suspects was additionally charged with going armed with intent and willful injury, both felony offenses.

Police also charged a third 15-year-old male and a 16-year-old on Thursday with rioting before both individuals were taken to the Central Iowa Detention Center in Eldora.

The incident remains under investigation with authorities noting additional charges are still possible.