NAIROBI (Reuters) - Burundian authorities have charged three schoolgirls accused of defacing a picture of President Pierre Nkurunziza, spokeswoman for the country’s Supreme Court, Agnès Bangiricenge, said on Thursday.

FILE PHOTO: Burundi's President Pierre Nkurunziza walks during a ceremony in tribute to the former late President Colonel Jean-Baptiste Bagaza at the national congress palace in Bujumbura, Burundi May 16, 2016. REUTERS/Evrard Ngendakumana/File Photo

The three girls were among seven school children arrested last week in Kirundo province, in Burundi’s northeast and some 200 kilometers from the commercial capital Bujumbura. Four others were subsequently released.

All were all accused of insulting Nkurunziza by scribbling over images of him printed in their school text books.

A regional court in Kirundo decided on Wednesday to detain the three further and proceed with a full trial, Bangiricenge said.

They will await trial in a nearby prison and could face up to five years in jail on conviction, a judge told Reuters on condition of anonymity.

“It is true that scribbling (on the president’s picture) is a punishable offence under the Burundian law but since it was committed by teenagers, I believe this is a mitigating circumstance,” David Ninganza, a children’s rights defender working for local group SOGEPAE, told Reuters.

“Those school children are not engaged in any political fights and need no political posts. That’s why judges have to consider all those issues in their investigations.”

School children have in the past been kicked out of school for similar offences, with some jailed and released.

In 2016, 11 children were jailed on accusations of defacing a photograph of Nkurunziza in a school text book.

In another incident in the same year, more than 300 students of a school in the capital’s Ruziba neighborhood were sent home after being accused of defacing Nkurunziza’s image.

Hundreds of Burundians have been killed in clashes with security forces and half a million have fled abroad since Nkurunziza announced in 2015 he would run for a third term in what his opponents saw as a breach of the constitution. He won re-election.

Early this month, the U.N. High Commissioner for Human Rights Michelle Bachelet said Burundi had forced the United Nations to shut its local human rights office after 23 years.

In 2016 Burundi suspended all cooperation with the U.N. human rights office in Burundi after a U.N.-commissioned report accused the Bujumbura government and its supporters of being responsible for crimes against humanity.

Bachelet said there were still credible reports of serious human rights violations in Burundi, including arbitrary killings, forced disappearances, ill-treatment, arrests and detention, and curbs on freedom of association, expression and movement.