SAO PAULO (AP) — The head of the prosecution task force investigating the largest corruption scandal in Brazil's history says next year's elections will be "the final battle" in the nearly four-year-long probe.

Deltan Dallagnol told reporters on Monday the general election could bring congressmen who want to continue to fight against corruption, or those who want to halt it "out of a sense of preservation."

The Car Wash probe has led to convictions of dozens of business executives and politicians. About half the current congress members face corruption probes.

Brazilians will vote for president, 513 members of the lower house of congress and two thirds of the 81-seat Senate in October.

The investigation has uncovered embezzlement and bribery through the Brazilian government, legislature and corporate world, especially in Petrobras, Brazil's state oil company.