Egypt arrests aide to barred presidential challenger after threat to 'expose Sisi' ahead of elections

Egyptian police have arrested the country's former anti-graft chief after he suggested that a presidential hopeful he campaigned for had documents implicating current leaders, his lawyer said.

Ali Taha told local news website Masr al-Arabia that Hisham Geneina was arrested at his Cairo home on Tuesday, in the latest development in a crackdown on opposition ahead of next month's presidential election.

Taha said that military prosecutors have decided to remand Genena in custody for 15 days pending the completion of an investigation.

Geneina was an aide to Sami Anan, a former military chief of staff detained after the army accused him of illegally announcing his intention to stand in the March election against President Abdel Fattah al-Sisi.

In an interview with HuffPost Arabi published late on Monday, Geneina said the damning material, held at a "secure" place abroad, could be released if any harm came to Anan.

"[Anan] has documents and evidence regarding all the major events in the country... they of course would change the course and condemn many", he said.

The documents Anan is claimed to have possessed "revolve around political events and crises Egyptian society has passed through" since the January 2011 uprising, Geneina said.

The military responded to Geneina's interview with a statement on Monday saying it had demanded an investigation against both Geneina and Anan.

Last month, Geneina was assaulted by three men near his home, sustaining serious eye and knee injuries as he was on his way to file an appeal contesting the removal of Anan's name from the list of presidential hopefuls.

In 2016, Geneina was sacked by Sisi as head of the Central Auditing Authority after being accused of exaggerating the cost of corruption in Egypt.

He is the latest election-related casualty in what appears to be an intensifying campaign against dissent ahead of the vote.

Sisi is all but certain to win next month's election.

His only opponent is the leader of a small party who campaigned for Sisi before announcing his bid.

Another rival, the Mubarak-era prime minister Ahmed Shafiq, withdrew from the race after his aides claimed he was deported to Egypt from the United Arab Emirates and held in a hotel.

Yet another potential candidate, military colonel Ahmed Qonsowa, was sentenced to six years in prison for illegally announcing his candidacy.

Egypt's opposition groups have called for a boycott of what they say are a 'farcical' election.