U.K. says Liverpool taxi blast was a bomb, raises threat level

British authorities raised the country's threat level to its second-highest rung on Monday, after police said a blast in a taxi outside a Liverpool hospital was caused by a homemade bomb.

Investigators said they were treating Sunday's explosion - which killed the suspected bombmaker and injured the cab driver - as a terrorist incident, but that the motive was unclear.

Counterterrorism police named the dead man as 32-year-old Emad Al Swealmeen. They did not give further details, though Britain's Press Association news agency and other media reported that he had not been on the radar of the security services.

The Joint Terrorism Analysis Centre raised the U.K. threat level from substantial - meaning an attack is likely - to severe, meaning it is highly likely, following the U.K.'s second fatal incident in a month. Conservative lawmaker David Amess was stabbed to death in October in what police said was an act of terrorism.

Prime Minister Boris Johnson condemned the “sickening attack” at Liverpool Women's Hospital and told reporters that the British people “will never be cowed by terrorism.”