By Ozgur Ayaydin and Mehmet Siddik Kaya

ANKARA

A Turkish soldier critically wounded in a PKK ambush in southeastern Turkey has succumbed to his injuries, an Anadolu Agency correspondent reports. 

Earlier, Turkey’s military said that two other soldiers had been martyred in the PKK attack which took place in the Sur district of the southeastern province of Diyarbakir. 

The deadly incident occurred during an ongoing military operation to fill trenches and to remove barricades set up by PKK terrorists to keep security forces out of the district. 

"Despite all interventions [in hospital], our two hero comrades [died] at 09.07 local time [0707GMT]," said the military in a statement. The third soldier died at Diyarbakir Military Hospital. 

Two police officers were also "critically wounded" the army said.

Sur, along with Cizre district of southeastern Sirnak province, are among areas that have been the focus of counter-terror operations and military curfews since early Dec. 2015. 

Turkish security forces have killed more than 600 PKK terrorists in total in the two districts since counter-terror operations began, according to a Turkish General Staff statement issued Saturday. 

The PKK - designated a terrorist organization by Turkey, the U.S. and EU - renewed its armed campaign against the Turkish state in late July. Since then more than 250 members of the security forces have been martyred.