British police announced the arrest of three men after a car exploded in front of Liverpool Women's Hospital, in the city centre, killing one man and injuring another on Sunday morning.
The three men, aged 29, 26 and 21, were arrested in Liverpool's Kensington district under the anti-terrorism laws, Greater Manchester Police said in a tweet.
The man killed in the blast has not yet been identified, the statement said. The injured man, who was driving, was in a stable condition in hospital.
Counter-terrorism police in the region were working closely with the Liverpool force, the statement added.
Merseyside police, who cover Liverpool, said in a separate statement that the blast had happened just before 11:00 am (1100 GMT).
"So far we understand that the car involved was a taxi which pulled up at the hospital shortly before the explosion occurred," said the statement.
They were keeping an open mind as to the cause of the blast, it added.
On Twitter, Prime Minister Boris Johnson praised the emergency services for their work on the incident so far.
Interior Minister Priti Patel tweeted earlier that police were keeping her up to date on developments.
"Our police and emergency services are working hard to establish what happened and it is right they are given the time and space to do so," she added.
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