The suspect in an assassination plot against Venezuelan president Nicolas Maduro has died after a mysterious fall from a window while he was in custody.
Opposition politician Fernando Alban, 56, was jailed for his alleged involvement in the explosion of two drones during a military parade attended by the South American leader.
Venezuelan uthorities said he killed himself by jumping out a window while in custody.
His party have claimed he was murdered.
Expressing concern, the United Nations human rights office have called for an independent investigation.
"We do indeed call for a transparent, independent investigation to clarify the circumstances of his death," said the organisation's human rights spokeswoman Ravina Shamdasani. "We understand there are conflicting reports on what exactly happened."
In a Twitter post, Néstor Reverol, Venezuela’s interior minister, said that while in the waiting room on the 10th floor of the headquarters of state intelligence agency SEBIN, Mr Alban had jumped from the window to his death.
That account differed from the one by chief prosecutor Tarek Saab, who said in televised statements that Alban had asked to use a bathroom and jumped from there.
The opposition First Justice party, to which Mr Alban belonged, said he was murdered.
It said that his arrest was due to statements he made at recent UN meetings in New York City denouncing humans rights violations in Venezuela.
Agencies contributed to this report
