Lawyers for a missing Dubai princess want the United Nations into intervene in her case.
And Human Rights Watch has also asked Dubai's ruling sheikh to reveal the whereabouts of his daughter after a French ex-spy and others say she fled the emirate, only to be arrested off the coast of India.
The statements mark the latest twist in the cloak-and-dagger drama surrounding the disappearance of Sheikha Latifa bint Mohammed Al Maktoum, who friends believe has been returned to Dubai after fleeing in late February.
She was detained on March 4 in a seaborne raid, witnesses said.
Sheikha Latifa's father is Sheikh Mohammed bin Rashid Al Maktoum, Dubai's ruler and the United Arab Emirates' Vice-President and Prime Minister.
"Failure to disclose the whereabouts and status of the princess could qualify as an enforced disappearance, given the evidence suggesting that she was last seen as UAE authorities were detaining her," Human Rights Watch said.
"The whereabouts of Sheikha Latifa is currently unknown. However, given the circumstances and reports in the media, it is believed that she is in the custody of the UAE authorities, detained against her will," Toby Cadman, of law firm Guernica 37 International Justice Chambers, told the Independent.
Guernica 37 has lodged an appeal with the UN Working Group on Enforced and Involuntary Disappearances, the UN Working Group on Arbitrary Detention and the UN Special Rapporteur on Torture.
"She is subject to 'enforced or involuntary disappearance' – and further, if it is confirmed that she is in the custody of the UAE authorities, she is being 'arbitrarily detained'," Cadman told the Independent.
Dubai has declined to comment publicly about Sheikha Latifa since AP reported in April on her disappearance . The Government's Dubai Media Office offered no immediate comment.
"UAE authorities should immediately reveal the whereabouts of Sheikha Latifa, confirm her status and allow her contact with the outside world," said Sarah Leah Whitson, Human Rights Watch's Middle East director.