Indigenous protesters in Peru have released more than 100 tourists they held on a riverboat in protest at earlier oil spills in the country's Amazon region.

"They are already returning to their places of origin," Tourism Minister Roberto Sanchez told reporters in Lima on Friday.

Peruvian, American, and European nationals were detained on the boat by the Cuninico community since Thursday.

On Friday the tourists and locals were released and transferred to another boat.

Angela Ramirez, a Peruvian cyclist who was among the tourists said there had been "a lot of anxiety, much fatigue" amongst the group.

She said they had slowly started running out of water and food during the 28-hour ordeal.

Oil spills have had health impacts

The leader of the Indigenous group, Watson Trujillo, said the Cuninico community took the "radical measure" to try to force the Peruvian government to assess the environmental damage from oil spills in the region.

"We have seen ourselves obliged to take this measure to summon the attention of a state that has not paid attention to us for eight years,'' Trujillo said.

He said oil spills in 2014 and again in September, this year "have caused much damage'' to people who depend on fish from the river as a significant part of their diet.

Peru's Health Ministry took blood samples in the region in 2016 and found that about half the tests from Cuninico showed levels of mercury and cadmium above levels recommended by the World Health Organization.

The community wants the government to declare an emergency to deal with the effects of oil pollution.

lo/ar (AFP, AP, Reuters)