Investigators are at the scene of a crash involving a light aircraft in Essex.
It came down in a field off Mill Lane, High Ongar, at about 12:30 BST on Tuesday.
Det Ch Supt Morgan Cronin, of Essex Police, said: “This is a serious incident and we understand it will cause concern in the local community.”
The Air Accidents Investigation Branch described the crash as an “accident” and sent inspectors to the site.
It is not yet clear if anyone has been injured.
People have been asked to avoid the area while emergency crews work at the scene.
Cronin said officers were making the scene safe, adding: “There will be a visible police presence as we deal with this incident.”