BOGOTA, Colombia — The U.N. High Commissioner for Human Rights expressed alarm Tuesday at the “staggering number” of social activists killed in Colombia despite a peace accord aimed at improving conditions in poor, rural areas.

According to the United Nations, 107 human rights defenders were killed in 2019, a worrying number that could grow to 120 as investigations are completed. At least 10 activists have been reported killed in the first two weeks of 2020.

“This vicious and endemic cycle of violence and impunity must stop,” said Marta Hurtado, spokesperson for the high commissioner.

The vast majority of the deaths happened in rural areas with higher-than-average rates of poverty and where illegal armed groups operate. Some of these areas were previously controlled by the Revolutionary Armed Forces of Colombia, the rebel group that signed an historic peace accord in 2016.

The United Nations pointed to challenges in implementing the accord, the presence of illegal armed groups in territory once controlled by the leftist rebels and the government’s military-focused response as all being partly to blame.

The landmark agreement ending over five decades of conflict includes lengthy chapters outlining ways for the government to establish a presence in remote regions where the illicit drug trade flourishes. While some advances including the building of new roads and efforts at crop substitution have taken place, those parts of the accord are proving to be the most difficult and long-term to bring into action.

Christine Armario is an Associated Press writer.