(CNN) State-sanctioned executions are on the rise in South Sudan and people who were children at the time of the crime are among those who have received the death penalty, according to a new report by Amnesty International.

Based on information compiled from legal professionals and government officials, Amnesty says the country has executed seven people, including one who was a child at the time of their offense, in 2018.

This represents the highest number of executions since South Sudan became the world's youngest nation following independence in 2011, according to Amnesty International.

Amnesty called the findings "extremely disturbing" and revealed worries about another 135 death row prisoners-- including at least one child and a breastfeeding mother -- who the group says were recently moved into facilities known for executions.

Since South Sudan broke away from Sudan seven years ago, the number of people on death row has doubled to 342 prisoners, according to the rights group.

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