Former army chief Abdel Fattah el-Sisi has won a landslide victory in the Egyptian presidential election, securing 93.3 percent of the votes cast, judicial sources have said.

His only rival, leftist politician Hamdeen Sabahi, got only 3 percent of the votes. He conceded defeat on Thursday after saying the vote was unfair.

"The election process in itself and the democratic goal in the election was violated and lacked impartiality. We cannot give any credibility and we cannot believe the figures declared until now about the participation of the voters in this election," Sabahi said.

Official election commission figures will likely be released next week but are not expected to change much due to the wide gap in results.

Egypt's presidential election was to be held over two days but was extended by another day amid concerns over low voter turnout. The poor turnout cast doubts about the level of public support for Sisi, who deposed the country's first elected president, Mohamed Morsi, in a coup last year.

Interim President Adly Mansour, installed by Sisi last July, said turnout was 46 percent, proclaiming it showed "a broad

consensus".

It was, however, much lower than the election that brought Morsi to power in June 2012.

Brotherhood boycott

Fireworks were set off in capital Cairo when results began to emerge. Sisi's supporters waved Egyptian flags and sounded car horns on the crowded streets of the capital.

A European Union team that observed the election said on Thursday that the vote was conducted "in line with the law," but regretted the lack of participation of some "stakeholders," a likely reference to Morsi's banned Muslim Brotherhood and youth dissident groups.

The Brotherhood, which has been designated a "terrorist" organisation by the military-installed interim government, boycotted the vote and hailed the low turnout.

"The great Egyptian people have given a new slap to the military coup's roadmap and... written the death certificate of the military coup," said its political arm, the Freedom and Justice Party.

All of the movement's main leaders are now in jail or exile, and Morsi is being tried on charges that could carry the death penalty.