This article is more than 1 year old

This article is more than 1 year old

A week after the deadly collapse of a mining dam in the Brazilian state of Minas Gerais, dozens paid tribute to the 110 victims killed and 238 who are still missing, while newly released video footage showed the moment that a powerful wave of waste began sweeping over everything in its path.

A ceremony was held at the site of the disaster around 1pm local time on Friday, the hour at which the dam breached on 25 January, unleashing a destructive torrent of reddish-brown mining waste.

Brazil dam collapse: bodies pulled from toxic mud as hope fades for survivors Read more

Backhoes stopped digging in the mud, and rescuers looking for survivors in the thick mine tailings all looked to the sky as 10 fire department and police helicopters released flower petals on the iron ore mining complex.

A priest also gave a brief mass in front of a tall pink cross that had been planted in the mud.

“It is totally devastated, it looks like there has been a war,” said Edvan Cristi, 23, who lost friends who worked at the mine.

In one video obtained by the Associated Press, cars can be seen driving around desperately trying to escape as a wall of mud approaches with dramatic strength.

The tailings, which contain toxic levels of iron oxide, plastered 250 hectares (620 acres) of Brumadinho and the Paraopeba river.

Vale SA, the company that ran and operated the dam, said the residues did not have dangerous levels of metals, but experts argue that the impact on the environment could be irreversible.

Facebook Twitter Pinterest Rescue workers attend a mass for victims the accident on 1 February. Photograph: Adriano Machado/Reuters

Authorities and environmental organizations have begun testing water quality around the mining complex, while state and federal authorities have told residents to refrain from using water directly from the Paraopeba or 100 metres around it.

The Paraopeba river flows into the much larger Sao Francisco river, which could also be contaminated.

Hundreds of municipalities and larger cities such as Petrolina, 870 miles from Brumadinho, get drinking water from the Sao Francisco river.

The wave of mud is currently moving toward the Sao Francisco at about 1km/h (.62mph), but officials hope the Retiro Baixo hydroelectric dam and plant complex about 185 miles from Brumadinho will prevent the mud from contaminating it.

The tailing is expected to reach the Retiro Baixo dam between 5 February and 10 February.