Temporary Detective Chief Superintendent Gordon Lang has urged the public to check on family and friends to make sure "everyone is safe" after the arrest of double murder suspect James Allen.
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Brussels' Zaventem Airport departure hall has reopened to the public, 40 days after twin suicide attacks killed 16 people.
A 21-year-old man accused of planning to travel to Syria and engage in "violent jihad" has appeared in court.
An Australian entrepreneur has publicly identified himself as the inventor of the digital currency Bitcoin.