ISTANBUL, Turkey — The group stormed the building Tuesday and took hostage Prosecutor Mehmet Selim Kiraz.
Kiraz was shot in the head during the standoff, according to the Associated Press.
He was rushed to hospital where doctors tried to save his life, Turkish President Recep Tayyip Erdogan said earlier Tuesday.
He later died from his injuries.
Earlier Report: Kiraz was investigating the killing of Berkin Elvan, who died in March last year after spending 269 days in a coma due to injuries inflicted by police in the mass protests of early summer 2013.
The gunmen are demanding an arrest of the police officer who allegedly killed the minor.
A photo was released on Twitter showing a gunman pointing a gun at the head of Kiraz against the backdrop of a flag of the illegal organization.
DEMANDS: (From Al-Jazeera):
The hostage-takers released a list of demands for the release of the prosecutor, saying that the officer who shot Elvan must appear on TV and confess his guilt.
The police officer must also be tried in a people’s court, not in the state courts, the list read.
Another demand was that the rights of those who attended rallies in solidarity with the Elvan family must be reinstated and that the prosecutions against them should be abolished.
The group also demanded a safe exit of the armed men behind the hostage-taking, and the formation of a negotiation team involving prominent figures that the DHKP/C would choose.
