CAIRO (Reuters) - A leading member of an opposition campaign which was until this week challenging Egypt’s President Abdel Fattah al-Sisi in upcoming elections was attacked and severely wounded outside his home on Saturday, his wife, lawyer, and a campaign spokesman said.

Hisham Genena, a former anti-corruption watchdog chief, was working to elect former military chief-of-staff Lieutenant General Sami Anan, the last challenger seen as a potential threat to the re-election of Sisi in elections slated for March.

Anan’s campaign was abruptly shuttered after he was arrested this week and accused of running for office without military permission.

Genena had just left his home in a suburb outside Cairo when two cars stopped him and five men attacked him with knives and sticks, Anan’s spokesman, Hazem Hosny, told Reuters. The identity of the men is unknown.

The Interior Ministry could not be immediately reached for comment.

“His knee is broken and he is bleeding from several parts of his body ... they were trying to kill him,” his wife, Wafaa Kedieh, told Reuters.

On Tuesday, an army statement read on state TV said Anan’s presidential bid amounted to “a serious breach of the laws of military service” because as a military officer he was required to end his service and get permission before seeking office.

As Egypt’s top auditor, Genena had stirred controversy by publicly concluding that government corruption has cost the country billions of dollars. He was sacked by Sisi in 2016.