Barack Obama added his name to world leaders who have condemned the deadly attack on a bus carrying Israeli tourists in Bulgaria.
"The United States will stand with our allies, and provide whatever assistance is necessary to identify and bring to justice the perpetrators of this attack," Obama said in a statement, calling the attack "completely outrageous."
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Mixed fortunes across the UK tomorrow. Still breezy across the north.
The Labour leader said socialist politics would not be put "back in a box" as he appeared on stage at the festival.
MPs and Lords have been left unable to access their emails remotely as a result of the attack.