A US spy seconded to GCHQ was reportedly stabbed last week by a suspected terrorist in the town where the British intelligence service is based.
A 29-year-old man has been arrested on suspicion of terrorism offenses after a woman was stabbed outside a leisure center in Cheltenham last Thursday night, counter terrorism police have confirmed.
Officials have until Thursday to question him.
The South East Counter Terrorism Police Service said the woman was “seriously injured”.
“She was taken to hospital for treatment and is in a stable condition,” they said.
The Daily Mail reported that the victim, who has not been formally identified, worked for US intelligence and had been seconded to GCHQ.
GCHQ declined to comment on the claims.
Counter-terrorism police said they could neither confirm nor deny the allegations.
Read more from Sky News:
GCHQ director resigns
US drone crash: What do we know about the collision with the Russian jet?
The woman was reportedly in a car in the leisure center parking lot when the suspect attacked her.
It happened just three miles from the sprawling, doughnut-shaped complex that houses GCHQ’s headquarters.
The stabbing was initially treated as attempted murder before the suspect was arrested again under terrorism legislation.
Gloucestershire Police Assistant Constable Richard Okoney said: “I would like to reassure anyone living locally or visiting the county that we believe this is an isolated incident and we are not aware of any wider implications for the public. threats. We are working closely with our partners in counter terrorism policing.
“We understand incidents of this nature can be concerning and we encourage people to contact us on 101 with any other information they may have about this incident.”