London resident Laleh Shahravesh is seen in a file family photo with her daughter. Detained in Dubai

London -- A British woman is facing possible jail time in Dubai for calling her ex-husband's new wife a "horse" in a Facebook post almost three years ago, according to CBS News partner network BBC News. Britain's Foreign Office confirmed to the BBC that it was "supporting a British woman and her family following her detention" in the United Arab Emirates.

The BBC and an international legal organization that works on behalf of people arrested in Dubai said Laleh Shahravesh, of London, fell victim to the Arab city-state's tough laws on online defamation -- and the British government's failure to make people aware of them.

Shahravesh, 55, was arrested at Dubai's airport after arriving to attend her ex-husband's funeral. Now she's apparently facing prosecution over comments she posted to Facebook in 2016, on photos of her ex with his new wife, at whom she directed an insult, calling her a "horse."

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The campaign group "Detained in Dubai" told the BBC that under cybercrime laws in the UAE, a person can be sentenced to prison or fined for defamatory statements online.

The BBC said Shahravesh could face up to two years in jail or a fine of about $65,000 -- even though she wasn't in the UAE when she posted the comments in question.

It is the new wife in Dubai -- described by Detained in Dubai as "quite vindictive really" -- who is pursuing the legal case against Shahravesh.

The group said Shahravesh flew to Dubai with her 14-year-old daughter, who was allowed to return to London and is now working with U.K. authorities to launch a legal appeal to her mother's detention.

A police officer stands at a security gate at Dubai Airport in a Oct. 10, 2018 file photo. Getty

The Londoner said, via Detained in Dubai, that she regretted lobbing the insults online three years ago but reacted in anger after learning that her husband of 18 years had remarried after just eight months via social media.

Shahravesh has been released from prison, according to Detained in Dubai chief executive Radha Stirling, but her passport has been seized by UAE authorities and she is currently living in a hotel.

"I am not allowed to leave Dubai. I have been to court once, where I was not allowed to defend myself," the group quoted Shahravesh as saying. "I am due in court again on Thursday the 11th of April and face a fine I can never pay plus jail... I am terrified. I can't sleep or eat. I have gone down two dress sizes because of the stress. And my daughter cries herself to sleep every night."

Stirling is representing Sharavesh legally in the U.K. She told the BBC that all the 14-year-old daughter wants "is to be reunited with her mother."

Stirling told the BBC that "no-one would really be aware" of the UAE's strict cyber libel laws, and accused the government's Foreign and Commonwealth Office (the equivalent of the U.S. State Department) of failing to warn British tourists.

The Detained in Dubai CEO said in a written statement that she had, "warned the British Foreign and Commonwealth Office that their advice to tourists is insufficient."

"When the UAE introduced Cybercrime laws, it rendered almost every visitor to the country a criminal," Stirling said. "Visitors to Dubai are rightfully unaware that they could be jailed for a facebook or twitter post made from outside the jurisdiction of the UAE, and made years ago."

On the Foreign Office website's "Travel Advice" page for the UAE, the British government does warn specifically that any online support for rival country Qatar can be an arrest-able offense in the Emirates, but only if visitors to the website follow a link to a second page on "local laws" are they warned about the broad anti-defamation rules.

On that page there is a warning that, "posting material (including videos and photographs) online that is critical of the UAE government, companies or individuals, or related to incidents in the UAE, or appearing to abuse/ridicule/criticise the country or its authorities, or that is culturally insensitive, may be considered a crime punishable under UAE law."