Brazil's Lula detained in corruption probe; Rousseff objects

By Brad Haynes and Anthony Boadle SAO PAULO/BRASILIA (Reuters) - Former Brazilian President Luiz Inacio Lula da Silva was briefly detained for questioning on Friday in a federal investigation of a vast corruption scheme, fanning a political crisis that threatens to topple his successor, President Dilma Rousseff. Lula's questioning in police custody was the highest profile development in a two-year-old graft probe centered on the state oil company Petrobras , which has rocked Brazil's political a