Nearly 4,000 coal miners have lost their jobs in Mozambique’s Tete province over the past year as mining firms such as Brazil’s Vale cut back due to lower prices, the African nation’s state news agency said on Thursday.

Vale, which operates an open cast coal mine in the northwestern part of one of the world’s poorest countries, shed 2,348 workers, said the head of Tete province’s mineral resources department Portasio Aurelio.

Lower coal prices have forced mining companies to cut costs and the province has lost 3,937 jobs in the past year, Aurelio added.

Unless the coal price recovers, companies will face further losses, he said, adding taxes collected from mining companies have declined in the first half of the year to a fraction of the government’s target.