"Counterterrorism officers are carrying out searches at three addresses in the Midlands as part of their ongoing investigation into a collision in Westminster this morning," the press release read.
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A Ford Fiesta collided with several cyclists and pedestrians earlier on Tuesday before crashing at high speed into a security fence outside the Houses of Parliament. Three people were injured in the incident, police said.
The driver of the car was arrested at the scene on suspicion of terrorist offenses. According to the press release, a 29-year-old man is a UK national. His vehicle remains at the scene.
UK Prime Minister Theresa May expressed her support for those injured and thanked the emergency services "for their immediate and courageous response."