A 38-year-old man has been arrested at Heathrow Airport in relation to the probe into the Manchester Arena attack which killed 22 people last month, police announced in a statement on Wednesday.

According to the statement posted by the Greater Manchester Police on their official Twitter account, the man was under suspicion of offences contrary to the Terrorism Act.

"The arrest was planned beforehand and there was no direct threat to the airport," said the police's statement. 

As of now, police have arrested 19 people in connection with the attack, of which 12 have been released without charges.

Therefore, a total of seven people still remain in custody for questioning.

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