Nine Costa Rica police officers were arrested in a series of 17 coordinated raids by the Judicial Investigative Police (OIJ) on Thursday, accused of conducting multiple, violent home invasion robberies throughout the greater San Jose metro area.

According to investigators, the officers are suspected in at least 10 violent home invasions, in which the officers – working as a group – would arrive in police vehicles and in uniform, force entry and threaten the occupants with their police-issued firearms.  The officers are accused of stealing tens-of-thousands of dollars in cash and valuables from their victims.

According to the OIJ, the officers had been under investigation since July 2015.

Agents were able to seize important evidence during the raids, including weapons, documents, cell phones, and more than US $30,000 in cash.

Three other suspects who are not police officers were also arrested in the raids, while a fourth suspect, a Colombian national who investigators say was in fact responsible for planning the robberies, remains on the run.

According to the OIJ, the Colombian man, identified by the last name Castro, directed the officers’ actions, including selecting the times and places of the assaults – typically on luxury homes.  Castro has a previous conviction in Costa Rica for drug trafficking.

Meanwhile, officials did not rule out the possibility that more police officers could be involved.