France's massive Algerian community turned out Saturday to vote in a presidential election widely expected to be won by ailing Abdelaziz Bouteflika, who is running for a fourth term.

Voting opened early Saturday for the some 815,000 ex-pat Algerians, France's largest immigrant group, who are eligible to vote in the elections.

A man was killed Saturday in the southern Algerian town of Ghardaia, the second fatality in less than 24 hours of ethnic violence between Berbers and Arabs in the region, local sources said.

A Berber in his forties was stabbed early Saturday morning, Hamou Mesbah, a senior member of the opposition Socialist Forces Front, told Agence France Presse.

Algeria's Abdelaziz Bouteflika, who is running for a fourth term in Thursday's presidential vote, is widely expected to win despite his frail health preventing him from even campaigning.

The 77-year-old has appeared only rarely in recent months, and his decision to seek a new mandate has provoked derision and drawn sharp criticism from senior political figures questioning his ability to rule after he suffered a mini-stroke last year.

The winner of energy-rich Algeria's presidential election must tackle a major problem facing the country -- its dependence on hydrocarbon revenues, which are used by the government to defuse social tensions and which are in decline.

Sporadic protests over poor living conditions came to a head in early 2011, as the popular uprising in neighboring Tunisia toppled a decades old-dictatorship.

Around a dozen people, including two policemen, were wounded Friday in fresh clashes between Arabs and Berbers near the southern Algerian town of Ghardaia, a medical source said.

The unrest erupted after the main Friday prayers outside a mosque in Berriane, 45 kilometers (28 miles) north of Ghardaia, APS news agency quoted the source as saying.

A protest group, founded just two months ago when ailing Algerian President Abdelaziz Bouteflika controversially decided to seek re-election, has livened up a lackluster campaign from which the incumbent has been entirely absent.

Activists of the Barakat (Enough) movement have made their mark by daring to argue publicly that the 77-year-old Bouteflika, who is too sick to take to the campaign trail himself, is unfit to govern.

Violence is threatening Algeria's presidential election campaign, independent media outlets warned Monday, after unrest forced the camp of ailing incumbent Abdelaziz Bouteflika's to cancel a weekend rally and bolster security.

"Incidents multiply at election meetings, Bouteflika is dividing Algerians," ran the headline of El Watan, fretting that "the sudden recourse to violence raises fears of the worst" while El Khabar, another Algerian daily, declared that "violence is threatening the campaign."

The bomber who targeted a bus in the Bulgarian Black Sea resort of Burgas in 2012, killing five Israeli tourists, was of Algerian origin and trained in camps in southern Lebanon, the Bulgarian daily Presa said Monday.

"The assailant was born in Algeria, lived in Morocco and was trained in camps in South Lebanon. He also studied at a Beirut university with the other two suspects," the newspaper quoted sources familiar with the investigation as saying.

Algerian police beefed up security and arrested about 20 people on Sunday at a campaign rally for President Abdelaziz Bouteflika's re-election, a day after violence ended a similar gathering.

Dozens of students hostile to the ailing 77-year-old's bid for a fourth term tried to demonstrate ahead of the rally in Tizi-Ouzou, in the mainly Berber region of Kabylie east of the capital.

Ali Benflis, the main challenger to incumbent Abdelaziz Bouteflika in Algeria's presidential election, on Sunday deplored violence that erupted at a rally for his rival east of the capital.

Campaigning for the April 17 election was launched two weeks ago, with the 77-year-old Bouteflika widely expected to clinch a fourth term without taking to the road due to health concerns.