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Court halts operations at 13 Vale dams; operations at major mine affected

(Adds details on injunction, Brucutu mine)

RIO DE JANEIRO, March 25 (Reuters) - A Brazilian court has issued an injunction ceasing operations at several tailings dams owned by mining firm Vale SA, the iron ore giant said on Monday, which will hit production at a major mine.

The injunction, issued in response to a motion by prosecutors in the state of Minas Gerais, requires the firm to paralyze operations at 13 dams. As a result, the company said, production at its major Brucutu mine will take longer than expected to come back on line.

In late January, a tailings dam burst at a Vale-owned mine in Minas Gerais, likely killing over 300 people. Coming just over three years after another deadly burst at a Vale-linked dam in the same state, prosecutors and other authorities have ratcheted up pressure on the firm.

On Thursday, Minas Gerais authorities had given the firm the go-ahead to restart operations at Brucutu, after halting operations there in early February.

The subsequent injunction, which occurred on Friday but became widely known via a Vale securities filing on Monday, will delay the restart of Brucutu, the firm said, without giving a specific timeline.

Brucutu has an installed capacity of 30 million tonnes of iron ore, or about 8 percent of the company's annual output. Mining operations at other mines, it said, will be unaffected. (Reporting by Gram Slattery Editing by Chizu Nomiyama)