British police have opened fired outside the Ukrainian embassy in London after the ambassador's car was deliberately rammed.
When police blocked the vehicle the driver rammed the car again, forcing officers to open fire and use a Taser, BBC News reports.
A man in his 40s was arrested and taken to hospital as a precaution.
"From the time I heard the shots until I got to the window, which took about 15 seconds, all these police cars were already there," witness Heather Feiner told the Press Association.
"I could see a police officer that fired the shots. I could see them pointing their gun at the car.
"From what I could see [the suspect] didn't appear to be struggling at that point."
Police said they don't believe the incident was terror-related.
"As is standard procedure, an investigation is now ongoing into the discharge of a police firearm during this incident," Supt Andy Walker told BBC News.
"While this takes place, I would like to pay tribute to the officers involved this morning who responded swiftly to this incident and put themselves in harm's way, as they do every day, to keep the people of London safe."