Police in the Canadian city of Moncton, New Brunswick are urging residents to stay inside with their doors locked as they continue the search for a gunman who killed three officers and wounded two more.
In a tweet, the Royal Canadian Mounted Police said:
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Scotland Yard said the male youths will appear in custody at Westminster Magistrates' Court on Saturday.
Windy this weekend with gales across northwestern parts of the UK. Rain spreading southeast.
Greater Manchester Police said "inquiries are ongoing to fully understand the circumstances of the incident."