Mexican voters started casting their ballots Sunday morning to choose the country's next president, 500 deputies and 128 senators in the presidential and congressional elections.

The polling stations opened at 8:00 a.m. local time (1300 GMT) and will close at 6:00 p.m.(2300 GMT) on Sunday.

The election authority has installed 143,151 boxes across the country and imprinted 82.68 million ballots for the election of president, and the same number for that of senators and federal deputies.

Mexico's Federal Electoral Institute is expected to announce the quick count results of polling stations at 11:45 p.m. (0445 GMT Monday), but the official count will continue until next week.