Local officials said a couple accused of adultery in northern Mali was executed in public by stoning on Tuesday for “violating Islamic law.”

The former mayor of the town of Aguelhok in Mali, who has joined an Islamist extremist group called Ansar Dine, reportedly ordered the killings, according to the Associated Press. A deputy of the National Assembly confirmed their execution on Thursday.

It was the first stoning in the area since 2012 when another couple was put to death for similar reasons. According to the local official who described the killings, the “adultery” for which the man and woman were killed simply involved living together without being married.

“The Islamists dug two holes where they put the man and the woman who lived maritally without being married. They were stoned to death. Four people threw stones at them until they died,” he said, as quoted by the UK Daily Mail.

Another official said the execution was carried out because the couple “violated Islamic law.”

“This is barbaric. The people who did this should be arrested and put on trial,” said Oumar Diakite of the Malian Association for the Defense of Human Rights. He denounced the stoning as “cowardly murder.”

France’s new president, Emmanuel Macron, is expected to visit Mali soon, to meet with French troops stationed in the country.