N’DJAMENA, Chad — Chad charged six French citizens with kidnapping after they tried to fly out 103 African children from the remote border region with Sudan, bandaging them up to look injured and claiming they were Darfur orphans in need of rescue.

The case threatens to impede aid efforts for hundreds of thousands of Darfur refugees by intensifying already deep local suspicions about the motives of humanitarian workers.

Seventeen Europeans have been detained since Thursday, when authorities blocked an attempt by a French group calling itself L’Arche de Zoe — Zoe’s Ark — to fly the African children to Europe, where they were to be placed with host families. The French Foreign Ministry and others have cast doubt on the claims by the little-known group that the children are Darfur orphans.

“According to initial information … there seem to be many Chadian children and even many who are not orphans,” a French Foreign Ministry spokeswoman, Pascale Andreani, told reporters in Paris yesterday. If convicted, the suspects, who were charged late Monday, face up to 20 years hard labor in a Chadian prison, Chad’s interior minister, Ahmat Bachir, said.

Three French journalists traveling with the group and seven Spanish citizens who worked for the Barcelona-based charter airline hired to fly the children out also were detained, as was a pilot from Belgium. The journalists and the Spaniards were charged with complicity, Justice Minister Pahimi Padacket Albert said.

Two of the journalists were covering the operation and a third was present for personal reasons, according to the media watchdog Reporters Without Borders.