In Buriticupu, about 1,200 people risk losing their homes, and residents have seen the problem escalate in 30 years

Authorities in a city in the Brazilian Amazon have declared a state of emergency after huge sinkholes opened up, threatening hundreds of homes.

Several buildings in Buriticupu, in Maranhão state, have already been destroyed, and about 1,200 people of a population of 55,000 risk losing their homes into a widening abyss.