A new report is shedding light on Rikers Island inmates who say they've been struck in the head by correction officers at the jail.
The internal report by the New York City Department of Health was obtained by the Associated Press.
It says nearly a third of Rikers prisoners who claimed they were injured by guards between April 2012 and April 2013 had suffered a blow to the head.
This tactic, which is known as a "head shot,” is supposed to be a last resort because it can be fatal.
The report also shows an average of three prisoners a day claim they have suffered injuries were caused by guards.
Prisoners rights advocates say the report shows that not enough is being done to curb violence at Rikers, which houses around 12,000 inmates.
Correction union president Norman Seabrook tells the AP that guards should use "whatever force is necessary to terminate an aggression."
He also says understaffing and a rise in gang activity make it harder for guards to manage violence at the jail.