WORLD IN BRIEF: Nigerian troops fire on youths

JOS, Nigeria -- Soldiers opened fire on a crowd after curfew and killed two people, witnesses said Wednesday, just days after more than 200 people including dozens of children were slaughtered in several mostly Christian villages nearby.

Hundreds of people swarmed the streets of Jos on Wednesday morning, where one truck's windshield was a spider web of bullet holes with the word ''rejoice'' scrawled on it.

Residents had tried to stop the truck late Tuesday from entering the town after curfew late Tuesday, fearing it was carrying fighters or weapons. People have accused police and military of failing to provide enough security to the villages that were attacked Sunday morning.

Doomsday vault hits 500K mark

OSLO, Norway -- Two years after receiving its first deposits, a ''doomsday'' seed vault on an Arctic island has amassed half a million seed samples, making it the world's most diverse repository of crop seeds, the vault's operators announced Thursday.

Cary Fowler -- who heads the trust that oversees the seed collection, which is 620 miles from the North Pole, said the facility now houses at least one-third of the world's crop seeds.

''In my lifetime, I don't think we'll go over 1.5 million. I'd be rather surprised if we go over a million,'' Fowler told The Associated Press. ''At that point, we'd have all the diversity in the world ... and the most secure samples.''

Located in Norway's remote Svalbard archipelago, the Svalbard Global Seed Vault is a safeguard against wars or natural disasters wiping out food crops around the globe. It was opened in 2008 as a master backup to the world's other 1,400 seed banks, in case their deposits are lost.

Scientists to fix climate report

UNITED NATIONS -- At a tumultuous time in U.N.-led climate negotiations, one of the world's most credible scientific groups agreed Wednesday to plug the recent cracks in the authoritative reports of the United Nations' Nobel Prize-winning global warming panel.

''We enter this process with no preconceived conclusions,'' said Robbert Dijkgraaf, a Dutch mathematical physicist who co-chairs the group, the InterAcademy Council of 15 nations' national academies of science.

U.N. Secretary-General Ban Ki-moon asserted ''there were a very small number of errors'' in the 3,000 pages of the beleaguered U.N. Intergovernmental Panel on Climate Change's last major synthesis of climate data in 2007.