The experts stated that they were “gravely concerned" for Mansoor's physical well-being and urged United Arab Emirates (UAE) authorities to give him adequate medical care, ensure detention conditions meet minimum UN standards and either offer him a retrial or release him, presstv reported.
“The poor conditions of his detention in the UAE, including prolonged solitary confinement, may constitute torture,” they said in a joint UN statement.
“Mansoor has allegedly been kept isolated in al-Sadr prison in Abu Dhabi with no bed or water in his cell and with no access to a shower. Although visits have been allowed, they are rarely offered,” the UN experts pointed out.
Earlier this week, the Beirut-based [Persian] Gulf Center for Human Rights (GCHR), of which Mansoor remains a board member, announced that the activist has suspended the hunger strike which he had gone on March 17 in protest at poor detention conditions and his trial procedure.
The GCHR added that Mansoor’s family has not been able to visit him regularly to check on his health or strike status.
On December 31, 2018, the UAE Federal Supreme Court upheld a 10-year prison sentence against the activist, and ordered him to pay a fine of 1 million dirhams (US $270,000).
Mansoor, an electrical engineer and poet, was arrested at his home in the Emirate of Ajman in March 2017. He was later charged with “publishing false information and rumors, promoting a sectarian and hate-inciting agenda, and using social media to harm national unity and social harmony and damage the country's reputation”.
In 2011, the Emirati activist was convicted of “insulting officials” and sentenced to three years in jail. He was released after serving eight months but was stripped of his passport and not allowed to leave the country.
Mansoor has campaigned for freedom of expression, civil and political rights in the UAE since 2006.
Rights groups, including Amnesty International and the Human Rights Watch, have called on the Emirati government in the past to release Mansoor, arguing that his detention goes against freedom of expression and opinion.
The Arabic-language al-Araby al-Jadeed news website, citing local activists, reported on May 4 that a terminally-ill Emirati cancer patient had died in prison after authorities in the country denied her adequate medical care.
The report said 42-year-old Alia Abdel Nour had died as a result of medical negligence and abuse at al-Wathba Prison in the UAE capital city of Abu Dhabi.
The Emirati woman was arrested on July 28, 2015, from her home in the UAE.
She was forcibly disappeared to an unknown location and held for four months without being allowed to communicate with her family and without the disclosure of any information about her fate or whereabouts to anyone.
Abdel Nour had her hands and feet shackled to a hospital bed day and night. Prison guards said last year that the chains would only be removed upon death, according to family members.