Earlier tonight, officers responded to a collision in Golders Green.
Videos of the incident and the emergency response have been shared online and we know local residents, and others, will want to understand what happened.
The update below sets out what we know at this stage.
Today we remember all those who lost their lives and those affected by the terrorist attack in London on 7/7 in 2005.
Our thoughts remain with the families as we recall the bravery of police officers and emergency service colleagues who responded that day.