Three scientists in China were fired for ethics violations last week, months after a Greenpeace report accused them of secretly testing genetically modified rice on schoolchildren.

The tests were conducted four years ago on 25 students between the ages of six and eight at a primary school in Hunan province, Shanghaiist reports. For their lunches, the children were given genetically modified “golden rice,” which had been nutritionally enhanced to address vitamin A deficiencies.

Greenpeace accused the scientists of secretly testing the rice on children in August.

China’s Center for Disease Control and Prevention said the children’s parents were given consent forms for the experiment, but were not told specifics about the experiment or notified that the rice was genetically modified. Three officials in charge of the experiment were fired for violating ethics protocols, the Center said in a statement last week.

No one is reported to have suffered any harm from the experiment, but the families of the 25 children will each receive 80,000 yuan ($12,817) in compensation for having been unwittingly enrolled in the experiment.