Two men linked to the Revolutionary People's Liberation Party-Front (DHKP-C) terrorist group were given aggravated life sentences on Thursday in the case of Turkish prosecutor Mehmet Selim Kiraz's killing.

The Istanbul 27th High Criminal Court sentenced Mustafa Koçak and Murat Canım to aggravated life sentences for attempting to overthrow the constitutional order.

The court separately sentenced the suspects to 27 years in prison for aiding in the murder of Kiraz, 12 years for depriving a public servant of his liberty using arms and three years for violating the firearms law.

Three other defendants — Mithat Öztürk, Deniz Özel, and Cengiz Özel — each received terms of between six and 11 years in prison on charges of aiding a terrorist organization.

The court ruled for the continued detention of remaining accused defendants, and for the continuation of judicial control for one other defendant.

On March 31, 2015, Turkey was rocked by an unprecedented crisis at a major courthouse complex in Istanbul. Kiraz, a prosecutor, was taken hostage by unknown gunmen who entered posing as lawyers.

The two suspected DHKP-C members released a haunting photo of him with a gun to his head on social media.

After about nine hours of negotiations between Turkish police and the two hostage-takers, gunshots rang out inside Kiraz's office in the Çağlayan courthouse complex and police units in position outside of the building rushed in.

Kiraz was killed by two DHKP-C militants, Şafak Yayla and Mustafa Doğruyol, who were killed in the ensuing clash with police. The incident raised concerns regarding the security of courthouses and the DHKP-C threat, as the terrorist group has stepped up attacks in recent years.

DHKP-C is responsible for a number of terror attacks in Turkey including the 2013 attack on the U.S. Embassy in Ankara, which left a Turkish security guard dead and a Turkish journalist injured.

The far-left group is listed as a terrorist organization by Turkey, the U.S., and the European Union.