A taxi driver has been arrested over the murder of British diplomat Rebecca Dykes in Lebanon, police in Beirut have said.
An official said the Lebanese suspect confessed that he had killed the 30-year-old, whose body was found early on Saturday by the side of a highway east of the Lebanese capital.
Police say the killing was not politically motivated.
Earlier, a local forensics officer told the Associated Press news agency that Ms Dykes, who worked at the UK embassy in the city, was strangled with a rope.
Authorities were investigating the exact cause of her death and whether she was sexually assaulted, the official said.
Lebanese media said choke marks had been found on the woman’s neck and that she had been raped. She also had a piece of string tied around her neck.
Sky’s Adele Robinson says local media reported that Ms Dykes – who had been due to fly home for Christmas – had been out in the Gemmayzeh area of Beirut on Friday night with work colleagues, and left a bar on her own at around midnight.
A family spokesman said they were “devastated by the loss of our beloved Rebecca”.
“We are doing all we can to understand what happened,” he said.
A friend of Ms Dykes – who spoke to Sky News on the condition of anonymity – added: “She was a very cautious, astute and highly intelligent woman. She had the highest level of security training.
“I know she followed procedures, especially in the job she did. She was very charming, sociable and dedicated to her work. She wasn’t the kind of girl to be walking around on her own. She was always in control.
“There are many people in Beirut who are angry at the lack of information released about her death, and have suspicions.”
According to Ms Dykes’ LinkedIn profile, she had been working as a programme and policy manager for the Department for International Development (DfID) on the UK government’s Conflict, Stability and Security Fund (CSSF) programme in Lebanon.
A DfID spokesman said: “Our thoughts are with Becky’s family and friends at this very upsetting time.”
“There is now a police investigation and the FCO (Foreign Office) is providing consular support to Becky’s family and working with the local authorities.”
The Foreign Office has said it is in contact with authorities in Lebanon.
“Following the death of a British woman in Beirut, we are providing support to the family,” a spokesman said.
“We remain in close contact with local authorities. Our thoughts are with the family at this difficult time.”
The whole embassy is deeply shocked, saddened by this news. My thoughts are with Becky’s family, friends and colleagues for their tragic loss. We’re providing consular support to her family & working very closely with Lebanese authorities who are conducting police investigation.
— Hugo Shorter (@HugoShorter) December 17, 2017
The British Ambassador to Lebanon, Hugo Shorter, tweeted his condolences saying the whole embassy was “deeply shocked” and “saddened”.
He said the embassy was “working closely with Lebanese authorities who are conducting police investigation”.
Under Lebanon’s CSSF programme, the UK Government has spent millions of pounds supporting the country’s armed forces to address “security threats originating from Syria”.
Cash has also been spent on preventing “illegal cross border activity” between Lebanon and Syria – an area where jihadists have been active – and assisting local policing.
Josie Ensore, the Daily Telegraph’s Middle East Correspondent based in Beirut, told Sky News: “It is extremely rare for any sort of foreigner to be attacked and there is very low-level crime in Beirut… I feel safer here than in London or New York, walking home or being alone.
“I think that’s why the British and American communities are very shocked about what’s happened because it really is a very rare thing to happen.”