Around 50 young women and girls have been missing since Boko Haram extremists attacked a village in northern Nigeria that is home to a girls’ boarding school, provoking fears they may have been kidnapped like those from the town of Chibok nearly four years ago.

Authorities had no credible information that those missing from the village of Dapchi were taken by Boko Haram, said Abdullahi Bego, a spokesman for the governor in Yobe state.

Some witnesses, however, recalled seeing girls being taken by the armed militants of the group that abducted 276 girls from the school in Chibok in April 2014.

“I share the anguish of all the parents and guardians of the girls that remain unaccounted for,” Nigerian President Muhammadu Buhari tweeted.

I would like to assure them that we are doing all in our power to ensure the safe return of all the girls.”

Armed Boko Haram fighters invaded Dapchi on Monday evening, forcing residents, including students of Government Girls Secondary school, to flee into the bushes.

Police and the state ministry of education had initially denied claims that students were abducted.

In a statement issued Wednesday, Bego said more than 50 of the 926 students were still missing. Earlier reports indicated about 90 were not in class Tuesday, suggesting some had returned within the past 24 hours.

Student Aishatu Abdullahi was among those who escaped on foot and spent the night hiding in an abandoned house.

“They were shooting guns and everyone was confused. Then we started running all confused,” she told reporters. “We saw some people pushing some of the students to enter their vehicles.”

“Many of us are traumatised,” she said, adding that the school had given students a one-week break after the ordeal. “But, in all honesty, I am not willing to come back here because we are scared of what could happen to us in the future.”

About 100 of the 276 girls abducted by Boko Haram from Chibok in 2014 are still believed to be with their captors. Some escaped, while others were released as part of negotiations.