Election officials in Cameroon are reviewing applications from 51 presidential candidates including long-time President Paul Biya, who filed his paperwork just before the midnight Sunday deadline.

The 78-year-old president is seeking another seven-year term, despite calls for his retirement after 29 years in office.

Among his challengers in the October 9 election is John Fru Ndi of the main opposition Social Democratic Front.

Fru Ndi ran in the country's 2004 election but received just 17 percent of the vote, while Mr. Biya won a landslide victory with more than 70 percent.

In 2008, Mr. Biya eliminated term limits from the constitution, triggering anti-government riots which left 40 people dead.

Officials from the ruling CPDM party said Sunday that the president is “answering the call of the people” to run again.

Official campaigning begins September 15.