A British police officer was shot dead inside a London police station early Friday while detaining a suspect, who also sustained a gunshot wound.

London’s Metropolitan Police force said the officer was shot at the Croydon Custody Center in the south of the city just after 2 a.m. He was taken to a local hospital where he was pronounced dead.

The 23-year-old man being detained is in critical condition in a hospital.

The force said no police weapons were fired.

It is rare for police officers to be shot and killed in the U.K., which has strict firearms laws.

Prime Minister Boris Johnson and other senior politicians expressed shock at Friday's death.

“We owe a huge debt to those who risk their own lives to keep us safe," Johnson said.\