At least four people are dead as a result of the terrorist attack outside the UK parliament, the head of counterterror policing said.

Earlier in the day, several people were killed and many were injured after a vehicle drove into a crowd on London’s Westminster Bridge near the UK Parliament building. One man was later shot by police after he stabbed an officer inside the Parliament compound.

London Metropolitan police said earlier in the day they were treating the events as terrorist incidents. The attack is currently being investigated.