Australian Jimmy Wilson is among 22 people charged by Brazilian prosecutors over their roles in a dam collapse that killed 19 people last November.

Twenty one of the 22 have been charged with qualified homicide, and face sentences of up to 54 years in prison. Wilson is a former BHP Billiton senior executive.

The charges follow what is now considered to be the largest environmental disaster in Brazil’s history.

The dam was at an iron ore mine run by by Samarco, a company half-owned by BHP Billiton, and its collapse released millions of tonnes of muddy mine waste, wiping out several small communities, leaving hundreds of people homeless and poisoning a major river.

Samarco, its co-owners BHP Billiton and Vale SA – as well as the Brazilian engineering company which certified the dam’s safety -have been charged with environmental crimes.

BHP, Vale and Samarco officials said in statements they rejected the charges. BHP said it has not been formally advised of the proceedings and that it rejected outright the charges against the company and those individuals who have been charged.

Before the case goes to trial, the charges need to be approved by a judge.

“BHP Billiton Brasil rejects outright these charges,” BHP said in a message to staff.

“Our priority is to fully defend the unfounded criminal charges against all of our people.”

Prosecutor Jose Adericido Leite Sampaio told reporters on Thursday at a briefing in Belo Horizonte, broadcast live by GloboNews, that executives at Samarco had clear awareness the dam could fail but ignored the risks and prioritised profit.

If convicted the accused, who include 16 Brazilians, two Americans, a South African, an Australian and a French citizen, could face sentences of up to 54 years, prosecutors said.

Homes lay in ruins after the burst dam flooded the small town of Bento Rodrigues.

The former chief executive of Samarco, Ricardo Viscovi, is among the accused. Under Brazil’s criminal code, qualified homicide is homicide aggravated by certain factors.

Following the dam collapse, thick red sludge flowed into one of Brazil’s main rivers, the Rio Doce, killing fish and fouling water supplies for hundreds of kilometres before reaching the Atlantic ocean.

Demonstrators perform during a Rio de Janeiro protest against the Brazilian mining company Vale, demanding that the company take responsibility for burst dam.

Before the case goes to trial, the charges need to be approved by a judge. Prosecutors filed the charges with a judge in Belo Horizonte, Brazil earlier in the day.

“These people were murdered,” Eduardo Santos de Oliveira, one of the prosecutors in the case, said of those who died.

Vale said in a statement that it would vigorously defend its executives and employees against the charges and that evidence shows that there was no knowledge that the dam could fail before the disaster occurred.

-with AAP