MEXICO CITY — Rescuers searching Tuesday for seven people missing after a dam containing mineral tailings burst at a mine in the northern Mexican border state of Chihuahua found one body that was not yet identified, state officials said.

Some 150 people joined the search over a 7-mile (12-kilometer) course through the mountains where the contaminated water rushed after the dam broke Monday at the Rio Tinto mine complex, the state government said in a statement.

In addition to those missing, two people were reported hospitalized in stable condition.

Gov. Javier Corral visited the site Tuesday and said the state's priorities were finding the missing and protecting the Tubares river at the bottom of the watershed.

Later, Luis Cuauhtemoc Guerra Chacon, state civil protection coordinator, said the mining residue was successfully diverted and had stopped about three miles (6 kilometers) from the Tubares river. The water supply was not at risk, according to the statement.

Mexico's federal environmental prosecutor's office said in a statement that it was investigating at the scene to determine how much material was released.

In an aerial inspection, investigators saw that the flow stopped naturally several miles before reaching the Fuerte river. The area's rough terrain makes about three-quarters of the streambed where the material flowed inaccessible, the statement said.

The release on Monday morning carried away heavy equipment, vehicles and workers who were involved in a containment project, the statement said. The mining company told environmental investigators that the released material was not dangerous, but the statement said testing would be conducted to verify that.

The Chihuahua state prosecutor's office said it had opened an investigation to determine what caused the release.

The gold and silver mine is in Cieneguita in the municipality of Urique. Aerial photographs provided by the state government show a white residue coating a long winding course through the mountains. Video captured at the scene showed a thunderous torrent of water rushing down a steep mountainside.

The mine's owner, Cluster Minero de Chihuahua, did not respond to requests for comment.