Some 2,500 metalworkers at a Renault car factory in southern Brazil went back to work on Monday, ending a four-day strike after winning a bonus to compensate for high inflation, Reuters said. A union spokeswoman told the news agency that Renault agreed to pay employees at its Sao Jose dos Pinhais factory in Parana state a one-time bonus of 500 reais ($US166) to be disbursed on May 30.