Journalist Shafik Rehman, arrested last year for allegedly plotting to abduct the prime minister's son, has left for London.
He was scheduled to fly to the UK on Thursday evening but was barred from boarding the flight as police did not receive any documents allowing him to leave the country.
Police later cleared him for travelling overseas after scrutinising documents.
Shafik, a dual citizen of Bangladesh and the UK, left Dhaka on Friday morning, said Shairul Kabir, member of BNP chairperson's media wing.
The journalist's wife Taleya Rehman is currently undergoing treatment in the UK.
Shafik was arrested on April 16 last year for allegedly plotting to abduct and murder Sajeeb Wazed Joy, son of Prime Minister Sheikh Hasina.
He was released on bail in September.
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