Activists in Nigeria staged demonstrations in Abuja and Lagos on Friday urging President Muhammadu Buhari’s government to ensure the return of almost 200 of the 275 school girls taken captive by extremist group Boko Haram in 2014.

In October 2016, the government had announced the release of 21 of the Chibok schoolgirls after negotiations with the extremist group. It had said another group of 83 girls would be released “very soon.” But no captives have been released since. The government said it cannot release details about the negotiations due to security reasons.

“It is deeply shocking that three years after this deplorable and devastating act of violence, the majority of the girls remain missing,” AP quoted a United Nations panel as saying. The government has refused to acknowledge another abduction of more than 500 children from the northeastern town of Damasak in November 2014, the news agency quoted a Human Rights Watch statement.

“It is still a nightmare to me. It is still fresh as if it happened last night. The government is trying, but I believe they can do more than what they are doing,” said Rebecca Samuel, whose daughter Sarah remains missing, AP reported.

The girls’ kidnapping had triggered a social media campaign, #BringBackOurGirls, in which several well-known personalities took part, including United States First Lady Michelle Obama.

The news agency said the extremist organisation has killed more than 20,000 people and displaced 2.6 million while triggering starvation in the region.