A pair of French journalists working on a documentary in New Guinea have been detained since last week by Indonesian authorities on the grounds that they don’t have journalist visas, France 24 reported Tuesday. Thomas Dandois, 40, and Valentine Bourrat, 29, could face up to five years in prison and a $42,000 fine.

The Indonesian government is known for cracking down on journalists reporting in New Guinea. The southeastern Asian nation controls the western half of the territory. The eastern half is the country of Papua New Guinea.

A police spokesman from Papua province said the two French journalists were arrested Thursday in Wamena with what the spokesman said were three members of an armed criminal gang, which France 24 noted is the phrasing Papua police use for the Free Papua Movement separatist group.

The journalism advocacy group Reporters Without Borders said Dandois and Bourrat were being illegally detained by Indonesian authorities in a statement released Monday. The group said the journalists “were covering the living conditions of the local population and separatists demands.”

“That Dandois and Bourrat were doing a report on Papua is beyond all question,” Reporters Without Borders Secretary-General Christophe Deloire said. “These two reporters are known for their integrity and honesty. Holding them for such a long time must be regarded as a violation of media freedom. We urge the authorities to release them without delay.”

Sulistyo Pudjo Hartono, the police spokesman, told Agence France-Presse Indonesian authorities were concerned that the French journalists’ “activities were part of a plan to create insecurity and instability in Papua.”

“The pair admit to working as foreign journalists for ... Arte," he added, referring to the Franco-German television channel. "But we are continuing to investigate who Valentine and Thomas are and their purpose in Wamena."