RIO DE JANEIRO — Prosecutors in Brazil on Tuesday charged the former president of the Brazil-based mining giant Vale and 15 other people with homicide, faulting them for negligence in a dam disaster that killed at least 259 people a year ago.

Those charged include Vale’s former chief executive, Fabio Schvartsman, and other senior officials employed by Vale and by a German firm hired to assess the stability of its dams. They were also charged with environmental crimes, as were the companies.

The announcement came days before the first anniversary of one of the deadliest mining disasters in years.

The dam in Brumadinho, in the state of Minas Gerais, was built to hold waste from an iron ore mine. When it burst on Jan. 25, 2019, the company cafeteria and other facilities were buried in a torrent of mud.