Cyclists have been warned to be vigilant around west London's Hyde Park after hooded teenagers strung a rope across a cycle path that led to a woman suffering neck injuries.
The woman told police she saw the youths holding a cord across a path near Speaker's Corner at 10pm on Tuesday.
According to the Evening Standard, the woman felt something hit her neck which caused her to gasp for breath.
She managed to maintain her balance, but later noticed she had rope burn on her neck, according to reports.
Police are warning cyclists and pedestrians in Hyde Park to be extra vigilant, with detective constable Mike Heaney labelling the incident a "extremely dangerous and foolish act that could cause serious injuries".
He said Westminster CID was "not aware of any other incidents".
No arrests have been made and enquiries are continuing.
Anyone with information on the incident is asked to contact Westminster CID.