A top jihadist has been killed in the Sinai Peninsula, security officials said Friday, ahead of next week's presidential election expected to sweep Egypt's ex-army chief to power on pledges to eradicate terrorism.
Two protesters were also killed as supporters of ousted Islamist president Mohamed Morsi clashed with security forces.
Shadi el-Menei, a senior commander of Egypt's deadliest militant group, Ansar Beit al-Maqdis (Partisans of Jerusalem), was gunned down in an ambush in his native Sinai, the officials said.
Word of his death, not immediately confirmed by jihadist sources, came on the last official day of campaigning for Egypt's presidential election.
Ex-army chief Abdel Fattah al-Sisi is expected to rout his sole rival, leftist Hamdeen Sabbahi, in the vote to be staged in the Arab world's populous nation on Monday and Tuesday.
There were conflicting accounts of who carried out Thursday night's ambush.
Some officials said civilians from the Sinai's heavily armed tribes killed Menei.
Others said local Bedouins tipped off security forces, who intercepted him and other militants as they prepared to bomb a gas pipeline.
Some Bedouin tribesmen have in recent months collaborated with security forces against militants.
Ansar Beit al-Maqdis has claimed some of the deadliest and highest profile attacks on security forces since the army overthrew Morsi last July.
They have included an assassination attempt against the interior minister in September, as well as frequent attacks on security forces in the group's Sinai base.
The US State Department designated the group a "foreign terrorist organisation" in April.
Before Morsi's ouster, Ansar Beit al-Maqdis mainly targeted Israel with attacks on the gas export pipeline through the Sinai to the Jewish state. In January, its fighters fired a rocket at Israel's Red Sea resort of Eilat.
Since Morsi's ouster, Ansar Beit al-Maqdis has escalated its operations, and the military-installed authorities say more than 500 people have died in the violence, mostly security personnel.
The group is thought to have been founded in 2011 following the Arab Spring uprising which ended president Hosni Mubarak's 30-year rule.
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Its command structure and funding sources remain shadowy and analysts said Menei was just one of several leading figures within the group.
The army has poured troops into the Sinai to tackle the militants, securing Israeli backing for the deployment in the sensitive peninsula, where troop numbers are restricted under the countries' 1979 peace treaty.
- Sisi urges high turnout -
"Vengeance is coming," Ansar Beit al-Maqdis warned Sisi earlier this year, and the group launched twin suicide bombings outside the South Sinai provincial capital Al-Tur on May 2.
Sisi is running on a pledge to stamp out the violence and has promised if he wins, there will be no place for Morsi's Muslim Brotherhood, whose top leaders are all in jail or exile.
In televised campaign appearances, he has played to the security credentials and strongman image that endeared Sisi to Egyptians weary of the turmoil which has ravaged the economy and vital tourism sector.
But his opponents say if he becomes president, Egypt is likely to see a return to the autocratic rule of the Mubarak years.
On Friday, Sisi urged Egyptians to vote in large numbers.
"You need to go down now more than any other time in (the country's) history... Go down, show to the entire world that there are 40, 45 (million) or even more" voters casting their ballots, Sisi said in an interview to four television channels.
And in a televised address to the nation, Sisi said: "Egypt is going through a decisive moment in its history.
"I am asking (the youth) that they go down and cast their vote regardless of who they want to vote for. I am speaking to all Egyptian men and women."
He also reiterated his backing for a controversial ban on all but police-sanctioned rallies. Protests by Morsi supporters have often sparked deadly street clashes.
Two people were killed and several wounded when Morsi supporters clashed with police after Friday prayers in Cairo and in Fayoum, a town southwest of the capital.
Thousands of Sabbahi supporters, meanwhile, gathered in a central Cairo square chanting: "We the revolution are with Hamdeen."
"We swear to God that symbols of corruption and despotism (from Mubarak era) will not return," Sabbahi, who is seen as a defender of the ideals of the 2011 revolution, told the gathering.
Also on Friday, newspaper columnist Fahmy Howeidy, a strong critic of Morsi's ouster, was barred from leaving for Spain, officials at Cairo airport said.