Brazil's central government on Saturday began distributing electronic voting machines to the nation's polling stations, television station Globo reported on Saturday morning.

The first boxes were delivered in the state of Sao Paulo, in the south of the country, according to the state government. Some 23,000 machines will be distributed from the capital to 2,000 polling stations, and in all 467,000 will be delivered across the nation.

Sao Paulo was the first to see such deployment because it is South America's largest city, with 11 million residents, according to data published by the state-run Brazilian Geography and Statistics Agency (IGBE).

In a separate report, Globo said that four of the machines selected at random would be used to test the whole system. These would be removed from their polling stations and fed previously prepared votes to check if there is any deviation from expectations.

Brazil has been using the electronic voting system since 1996, both for public elections and legislative voting. The nation is set to choose 622 officials in Sunday's general elections, including a new president, 27 governors, 81 senators and 513 deputies for federal and regional legislatures.