A member of Nigeria's Islamist Boko Haram sect on Saturday claimed responsibility for a wave of attacks that killed at least 63 people in the northeast of the country the day before.

"We are responsible for the attack in Borno (state) and Damaturu," Abul Qaqa told an Agence France Presse correspondent by phone.

A blast went off Saturday along a road in the world's largest refugee camp in eastern Kenya near the border with Somalia, but no one was injured, officials said.

The explosion appeared to be minor and one of the officials said if it turns out to be an explosive device planted by insurgents it may have been improperly wired. The two officials spoke on condition they weren't identified.

A rare magnitude 4.7 earthquake shook the central U.S. state of Oklahoma early Saturday, the U.S. Geological Survey reported.

The epicenter of the tremor, which occurred at 2:12 am (0712 GMT), was located nine kilometers (six miles) north of the town of Prague, the agency said.

A Pakistani anti-terror court Saturday indicted two police officers and five alleged Taliban militants over the 2007 assassination of former Prime Minister Benazir Bhutto, a prosecutor said.

Nobody has been convicted or jailed for Bhutto's assassination on December 27, 2007, in Rawalpindi, a garrison city near the capital Islamabad, in a gun and suicide attack after she addressed an election rally.

A group of 21 North Koreans including women and children have been found adrift off the South's western coast, military authorities said Saturday.

A five-ton wooden boat with the group on board was spotted by sailors on a South Korean Navy vessel in the Yellow Sea on Sunday, the Joint Chiefs of Staff said in a press statement. Earlier reports said they were found Tuesday.

Six people were killed on Friday when the Italian port city of Genoa was hit by flash floods during heavy rainfall, including one woman who was apparently crushed by cars being swept away by the water.

"There have been six deaths," said the local prefect, Francesco Musolino.

The top leader of Colombia's main rebel group, the bookish ideologue Alfonso Cano, was killed Friday in a military raid in the country's southwest, authorities said.

The death was a major victory for President Juan Manuel Santos, coming just over a year after the military killed the rebels' field marshal. It was anything but a fatal blow, however, to the nearly half-century-old peasant-based insurgency.

Several explosions ripped through Nigeria's troubled northeastern and predominantly Muslim city of Maiduguri on Friday, including a suicide bomb attack on military offices, the army said.

Another one of the bombs went off outside the offices of the state intelligence agency, a military spokesman in the city said.

Around 1,500 foreign tourists have been stranded in the Everest region due to heavy fog that has halted flights from the only airstrip serving the area, a local aviation official said on Friday.

Thousands of foreign tourists visit the Everest region during the peak tourism season late in the year.

Territorial tensions in the South China Sea could explode into "full-scale conflicts" unless quarrelling neighbors abide by international law, a Vietnamese diplomat warned on Friday.

Dang Dinh Quy, president of the state-run Diplomatic Academy of Vietnam, told a Hanoi conference on maritime disputes that the significance of the sea to regional peace was becoming increasingly evident.