BRUMADINHO, Brazil -- A week after the collapse of a mining dam in the Brazilian state of Minas Gerais, dozens paid homage Friday to the 115 people killed and 248 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 1 p.m. local time, the hour at which the dam breached on Jan. 25, unleashing a destructive torrent of reddish-brown mining waste.
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 23-year-old Edvan Cristi, 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 gush of mud approaches with dramatic strength.
A spokesman for the Minas Gerais Fire Department said after the ceremony that authorities were not calling off the search for bodies although no one had been found alive since Saturday.
On Friday, operations seemed to enter a new phase as firefighters began excavating the mud with heavy machinery. So far, efforts have been focused on finding bodies closer to the surface and did not involve backhoes.
The mayor of the nearby city of Brumadinho, Avimar de Melo Barcelos, told reporters that his municipality remained deeply disrupted because main roads were still blocked by mud. He said rural residents, who account for about 40 percent of the municipality, could not reach the city center.
Aside from the human tragedy, de Melo Barcelos stressed that the city would need financial help from the federal government as nearly 35 percent of taxes collected for the municipality come from mining activities.
"We are a mining town. If we lose that 35 percent of tax collection, we're not going to be able to attend to basic social services," the mayor said, citing costs related to health and education.
The tailings, which contain toxic levels of iron oxide, plastered 252 hectares (623 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.
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-meters (109 yards) 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, 1,400 kilometers (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 1 kph (.62 mph), but officials hope the Retiro Baixo hydroelectric dam and plant complex about 300 kilometers (185 miles) from Brumadinho will prevent the mud from contaminating it.
The tailing is expected to reach the Retiro Baixo dam between Feb. 5 and Feb. 10.
A peaceful walk in homage to the victims took place on Friday evening in Brumadinho. Dressed in white, hundreds of mourners took part in the commemorative march through the city.
Relatives and friends of the victims set up an altar, leaving flowers and lighting candles along with notes of the names of the dead.
"This tragedy will be remembered not just here but all over Brazil," said 23-year-old Jonatan Silva Santos, who lost friends that worked at Vale. "This city is small, each person that we lost is like a member of our family."
Marcelo Silva de Sousa reported this story in Brumadinho and Diane Jeantet reported from Rio de Janeiro.