April Jones' acting headteacher, Gwenfair Glyn, of Machynlleth Primary School, said on Friday that this week had been "the hardest in the school's history".
Reading from a statement, she said: "The whole school, pupils, staff and parents, are desperately worried by today's news, but we are still clinging to the hope that April will be returned to us.
"As more time goes on we are becoming increasingly concerned for her safety, but we refuse to give up hope, and are praying that April is alive.
"This week has been the hardest in the school's history, an emotional rollercoaster, but everyone has rallied around and provided tremendous support for the school and its community, and we are grateful for that.
"Our thoughts are with April's family and friends at this desperately worrying time, and we will give them whatever help and comfort they need."
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