Boko Haram militants attacked a village in restive northern Nigeria, killing 17 people and setting houses and cars alight, the local government said Sunday.

Among the dead were Muslim worshipers shot as they prayed in the village mosque, said Abdullahi Bego, spokesman for the governor of the troubled state of Yobe.

One person was killed and 14 wounded Sunday in a series of apparently co-ordinated blasts -- including a car bomb -- in a major town in Thailand's insurgency-hit south, the army said.

Four explosions rocked Yala, a provincial capital, on Sunday afternoon including a device hidden in a car which destroyed the vehicle and damaged several nearby buildings.

Activists chanting "Russia!" broke through police lines Sunday and stormed several government buildings in eastern Ukrainian regions seeking independence from Kiev following last month's fall of a Kremlin regime.

Clashes in Donetsk and similar rallies in the heavily Russified cities such of Lugansk and Kharkiv provided another reminder to the untested pro-Western leaders in Kiev of the monumental task facing them after their February 22 overthrow of president Viktor Yanukovych.

Gunmen believed to be Fulani herdsmen stormed a meeting in northern Nigeria's Zamfara state and killed 30 people, police said Sunday.

"Thirty people were killed and several others injured," Zamfara state police spokesman Lawal Abdullahi told Agence France Presse.

Voting was under way in Costa Rica on Sunday, where historian and former diplomat Luis Guillermo Solis faced no opposition in the country's presidential run-off election.

His lone rival in the race, Johnny Araya, dropped out last month after polls showed he would be soundly defeated, giving Solis a glide path towards victory in the election to lead this country of some five million people.

Rwanda on Sunday told France to face up to the "difficult truth" of its role in the 1994 genocide, amid a major diplomatic spat on the eve of commemorations marking the 20th anniversary of the killings.

French Justice Minister Christiane Taubira pulled out of attending Monday's events after Rwandan President Paul Kagame repeated his accusation of French "participation" in the murder of 800,000 ethnic Tutsis.

Cameroon's security forces Sunday were sweeping the remote northern region where two Italian priests and a Canadian nun were kidnapped by suspected Boko Haram gunmen, a local government official said.

"We are everywhere. We have been on the ground since the abduction," local governor Awa Fonka Augustine told Agence France Presse without elaborating.

Four Iranian soldiers abducted by Sunni extremists have returned home after being held for two months in neighboring Pakistan, state media on Sunday cited the intelligence ministry as saying.

The ministry did not address the fate of Jamshid Danayifar, a fifth soldier abducted alongside his fellow border guards on February 6.

A roadside bomb hit a truck carrying full ballot boxes in northern Afghanistan Sunday, killing three people a day after the country voted for a successor to President Hamid Karzai.

Eight boxes of votes were destroyed in the blast, which came as the three leading candidates voiced concerns about possible fraud.

Preparations in Rwanda Sunday for the commemorations for the 20th anniversary of the genocide were overshadowed by a major spat with France amid renewed allegations that Paris was complicit in the killings.

The French government announced that it was pulling out of Monday's events after Rwandan President Paul Kagame again accused France, an ally of the Hutu nationalist government prior to the 1994 killings, of having helped the murder of 800,000 ethnic Tutsis take place.