Istanbul, Turkey(CNN) Seven Turkish soldiers and one civilian personnel were killed in Syria on Sunday, Turkey's first fatalities as a result of direct confrontation between the countries since the start of Syria's civil war in 2011.
The Turkish Defense Ministry released the latest death toll on Tuesday. Several other troops had been also wounded in northwest Syria's Idlib province after they came under heavy artillery fire from the Syrian government, according to an earlier statement from the ministry, which specified that the troops were reinforcements.
On Monday, Turkish President Recep Tayyip Erdogan said up to 35 Syrian government soldiers had responded and pledged further retaliation.
Erdogan said up to 40 Syrian targets were being considered as part of the operation, and warned Russia -- the most powerful backer of Syrian President Bashar al-Assad -- to "not stand in our way."
"We told the Russian authorities you are not party to this it is totally the regime and do not stand in our way. Because we have martyrs, we cannot remain silent. We will continue to respond, including with our F-16s, our howitzers, our artillery, it is all in the field firing on the targets determined by our national intelligence," Erdogan said.
Russia's military said Monday that Turkey had not given advance warning of Turkish troop reinforcements in Idlib.
"Overnight from February 2 to 3, units of the Turkish forces conducted maneuvers inside the Idlib de-escalation zone without giving notice to the Russian side and came under the fire of Syrian government troops on terrorists in the area west of the settlement of Saraqib," the Russian Center for Reconciliation of the Opposing Sides in Syria said, according to state-run news agency RIA Novosti.
Turkish soldiers are in the last rebel-held area of Syria as part of a 2018 de-escalation agreement between Ankara and Moscow. The Syrian government has mounted an aggressive air campaign in Idlib in recent weeks, amassing troops along strategic highways leading to the rebel enclave.
On January 12, Russia and Turkey announced a ceasefire that has failed to end the violence.
Syrian government attacks killed 20 people in opposition-held parts of northwest Syria on Sunday and Monday, according to the volunteer rescue group, the White Helmets.
Nine were killed in an attack on a vehicle carrying members of the same family in the western countryside of Aleppo on Monday. An airstrike on a house in Idlib also killed eight on Sunday, according to the rescue group.
The recent violence has pushed people out of multiple towns. Syria announced the capture of the opposition-held city of Maraat Al Nouman on Thursday.
UNICEF estimates that more than 300,000 people have been displaced since December and that 1.2 million children are in desperate need.
The Syrian government and Russia deny targeting civilians and say they are targeting terrorists, pointing to the dominance of Hayat Tahrir Al Sham (HTS), a former al Qaeda affiliate, in the area.