Lusaka - Zambia's opposition leader Hakainde Hichilema on Sunday blasted the national election commission for slow progress in releasing results from last week's closely-fought presidential vote.Hichilema, the leader of the United Party for National Development (UPND) who has alleged fraud in Thursday's vote, demanded to speak to the commission's chairperson at its headquarters where the ballots are being counted, but he was blocked by police.So far results from only 69 out of 156 constituencies have been released. The electoral commission had initially indicated that results would be announced within 48 hours of the close of voting, and no explanation has been given for the delays."Why are they taking this long?" asked Hichilema, a wealthy businessman who is making his fifth bid for the presidency.Lungu is currently slightly ahead on 699 960 votes - with his victories including the capital Lusaka - with Hichilema close behind on 644 132. The other seven presidential candidates are far behind.Copper-rich Zambia is usually known for its relative stability, but the run-up to the vote was marked by weeks of clashes between supporters of the UPND and President Edgar Lungu's Patriotic Front (PF).Lungu took power only last year when he beat Hichilema by less than 28 000 votes in a snap election following the death in office of president Michael Sata.PF spokesperson Frank Bwalya dismissed Hichilema's visit to the vote-counting centre as a publicity stunt."By going to the commission he wanted to force the police to arrest him," said Bwalya.He blamed Hichilema's party for the delays, saying they had raised numerous complaints with the electoral commission."They have declared themselves the winners," he said.When asked about the delays, Lungu's spokesperson Amos Chanda said in a statement that the president was allowing the authorities "necessary room to do their job".Lungu's short term in office has been marked by the falling price of copper, the country's key export, with inflation rising to over 20%.Recent constitutional changes require the winner to secure more than 50% of the vote, meaning a run-off is possible should neither Lungu nor Hichilema secure a majority in the first round.The presidential, parliamentary and local election also included a constitutional referendum on amending the bill of rights.