Amnesty International says Iranian authorities are subjecting Belgian aid worker Olivier Vandecasteele to enforced disappearance, torture and other ill-treatment.

In a statement released on Monday, Amnesty International urged all states whose nationals are or have been detained at any point in Iran to promptly examine whether the deprivation of liberty amounts to an act of hostage-taking, and if so, take all appropriate measures to ensure accountability.

“He is held in solitary confinement in a windowless basement cell and is denied access to adequate healthcare and fresh air,” added Amnesty.

Additionally, his family and lawyer, as well as Belgian consular authorities, are unaware of his exact whereabouts.

Amnesty has warned that the Islamic Republic of Iran has kept this Belgian citizen as a "hostage" to exchange him with Asadollah Asadi, an Iranian diplomat.

Asadi has been sentenced to 20 years in prison for “attempted murder and involvement in terrorism” for his role in plotting to bomb a gathering of the MEK near Paris in 2018.

On 10 January 2023, Iranian state media announced that Vandecasteele was sentenced to 40 years in prison and 74 lashes, amidst indications that the Iranian authorities are holding him hostage to compel Belgian authorities to swap him for a former Iranian official imprisoned in Belgium.

Currently, at least 16 foreign citizens, most of whom dual nationals, are detained in the prisons of the Islamic Republic.