KHARTOUM, April 12 (Xinhua) -- Sudanese voters began to cast their votes on the second day of polling on Monday in the first multi-party elections in the country in more than 24 years.

The second day of polling is seen as a real challenge for the National Elections Commission (NEC) to prove its ability to overcome what it calls the "technical and administrative mistakes" in the first day of polling

On Sunday, the NEC acknowledged mistakes in voters' lists and some candidates' names, but said these mistakes were corrected.

In the meantime, many parties are demanding an extension of polling.

The Sudan People's Liberation Movement (SPLM) on Sunday asked for an extension of voting in the southern part of the country due to mistakes in the polling process.

Susan Jambo, a senior official responsible for the SPLM's election campaign, told Xinhua in Juba, the regional capital of southern Sudan, that they had found a lot of mistakes since the polling process started.

The chairman of Khartoum State's National Congress Party (NCP), Abdul-Rahman al-Khader, also demanded an extension of polling, local newspapers reported Monday.

More than 16 million Sudanese voters started casting their votes on Sunday to choose their representatives for the presidency, state governors, the president of southern Sudan and legislative councils.