PKK terrorists attacked Turkish military units with mortars and rocket-propelled grenades on Tuesday in southeastern Turkey, sparking clashes that killed 20 terrorists and eight soldiers, authorities said.
Another 16 soldiers were wounded in the attack in the Daglıca area of Hakkari province, which borders northern Iraq's Kurdish areas, the governor's office in Hakkari said.
"We condemn bloody attack in Hakkari in the strongest possible terms," the ambassador said in a statement the embassy released on Tuesday. Ricciardone's remarks came ahead of a meeting between Turkish Prime Minister Recep Tayyip Erdogan and US President Barack Obama on the sidelines of the G-20 meeting in Mexico.
Ricciardone said none of political or religious views could justify terrorism, adding that the US, who listed the PKK as a terrorist organization, will continue support Turkey's struggle against the PKK.
Meanwhile, leader of the Iraqi Kurdish regional government Massoud Barzani also condemned the killings.
Barzani said in a message that he "strongly condemned" the attack, adding that "attacks and clashes hurt all sides and damage peaceful efforts."
The PKK is fighting for autonomy in southeast Turkey. Tens of thousands have died since it took up arms in 1984.
A similar terrorist attack in the same area in late 2007, when 12 Turkish soldiers died, triggered an eight-day incursion by the Turkish military into Iraq in February 2008. Terrorists use northern Iraq as a base to launch attacks on Turkish troops.