(Adds detail on accusations)

RIO DE JANEIRO, June 9 (Reuters) - Brazil's federal police accused on Thursday mining company Samarco, a joint venture between Vale SA and BHP Billiton, of willful misconduct in relation to a deadly dam burst last November, saying the company had ignored clear signs the dam was at risk of collapsing.

Police said Samarco had skimmed on safety spending, focusing instead on increasing production despite obvious indications, such as cracks, that the dam was in danger of a breach.

As well as Samarco, police accused Vale because it deposited its own mining waste in the dam, and VogBR, the service company that checked the safety of the dam. Eight executives were also accused, although their names were not disclosed by the police.

Samarco said in a statement it rejected any speculation that it was aware of an imminent risk of collapse at the dam, which held waste known as tailings from its iron ore mine.

"The dam was always declared stable," the company said, adding that increases to the dam's size were done in accordance with the project's design.

The dam's height was below the size allowed by its licensing when it collapsed, Samarco said.

All of the accused, excluding one individual, were first informed by the police in January.

Although the police have not disclosed names, Vale said in a statement it "rejected forcefully the accusations against one employee," saying he was never responsible for the dam's management. VogBR did not immediately respond to requests for comment.

With the police investigation now complete, the case will be passed to prosecutors to decide whether to press charges.

(Reporting by Marta Nogueira and Stephen Eisenhammer; Editing by Matthew Lewis and Bernard Orr)