A prominent Emirati human rights activist was detained by UAE authorities in the early hours of Monday, according to a press release published by a rights group.
Ahmed Mansoor, who was awarded the 2015 Laureate Martin Ennals Award for Human Rights Defenders, was arrested by police in Dubai on Monday and transported to an unknown location, the statement said.
Sources suggest the rights activist' was arrested shortly after signing a letter addressed to the Arab League summit, "calling to release prisoners of conscience and promote and protect human rights in the Arab world".
Mansoor has previously been detained by UAE authorities for his work promoting human rights and was placed under a travel ban by authorities.
The Emirates Centre for Human Rights accused the UAE of launching "a new assault on freedom of expression" whilst Human Rights Watch's Nicholas McGeehan described Mansoor's arrest as "gut wrenching".
"The ICFUAE strongly condemns the arrest of human rights defender Ahmed Mansoor," a press statement published on Monday said.
"This demonstrates that the UAE authorities have a cavalier attitude towards freedom of expression and his detention serves no purpose other than to stifle that freedom. We urgently call for his immediate release."
In November, Human Rights Watch said GCC states have deployed surveillance technology to track and monitor citizens' online activity since the Arab uprisings of 2011.
This software can enable a government to access emails, text messages and potentially passwords, and can allow authorities to turn on a phone or laptop's camera and microphone to take pictures or record video and conversations without the owner's knowledge, research by Citizen Lab found.
All GCC States have also expanded existing legislation and announced new laws which further curtail free expression and punish free speech they deem "criminal", particularly online, HRW added.
"Gulf states are intimidating, surveilling, imprisoning, and silencing activists as part of their all-out assault on peaceful criticism, but they are seriously mistaken if they think they can indefinitely block Gulf citizens from using social and other media to push for positive reforms," Whitson said.
Human Rights Watch launched a website campaigning against the harassment and detention of dissidents who criticise Gulf governments online.
The profiles of 140 activists who have spoken out against their governments and subsequently been punished for their views are featured on the site, as HRW urges reforms.
"The Gulf states have engaged in a systematic and well-funded assault on free speech to subvert the potentially transformative impact of social media and internet technology," said Sarah Leah Whitson, HRW's Middle East director.
"Instead of hauling off their peaceful online critics to jail, Gulf governments should expand debate among members of society and carry out the much-needed reforms that many of these activists have demanded for years."