In the four-minute film, released by human rights organization Reprieve, Bey purportedly undergoes the feeding in a manner consistent with the military’s standard operating procedure as outlined in a document obtained by the newspaper.

More than 100 detainees at Guantánamo are on a hunger strike to protest their indefinite detention.

The Obama administration has been criticized by Republicans and Democrats alike for force-feeding many of the protesters, some of whom have been striking since February.

Sen. Dianne FeinsteinDianne Emiel FeinsteinDHS chief takes heat over Trump furor NSA spying program overcomes key Senate hurdle Democrats will need to explain if they shut government down over illegal immigration MORE (D-Calif.) last month called on Defense Secretary Chuck HagelCharles (Chuck) Timothy HagelHagel: Trump is 'an embarrassment' Tax cut complete, hawks push for military increase Pentagon documents hundreds of serious misconduct cases against top brass MORE to stop the force-feeding, saying it violated international norms and medical ethics.

“Hunger strikes are a long known form of non-violent protest aimed at bringing attention to a cause, rather than an attempt of suicide,” Feinstein wrote in a letter to the Pentagon chief. “I believe that the current approach raises very important ethical questions and complicates the difficult situation regarding the continued indefinite detention at Guantánamo.”

President Obama has tried to close the facility at Guantánamo and transfer detainees to U.S. prisons, but was blocked by Republicans and has been unable to find other countries willing to accept the prisoners.