At least one girl is killed and another six students are injured, two of them seriously, following a bomb blast outside a school in the southern Italian city of Brindisi.

Concerns about whether debt-laden Greece will be forced to pull out of the eurozone, and what that would mean for a weakened European economy is the first topic on Saturday's agenda at the Group of Eight summit hosted by U.S. President Barack Obama, a senior administration official said.

Spain's government calls for calm a day after rating agency Moody's downgraded 16 Spanish banks in the latest sign of distress in Europe.