An Israeli attack killed six people in southern Syria on Tuesday, Syria's foreign ministry said, after the Israeli military said its troops had clashed with gunmen who had opened fire on them.
Israeli troops occupying the area clashed with local residents, Syrian state media and a war monitor reported.
Israeli military spokesperson Avichay Adraee said troops fired back at gunmen who attacked them, before launching a drone attack.
Syrian state-run news agency SANA said several people were wounded, including a woman.
The Britain-based war monitor the Syrian Observatory for Human Rights put the death toll at seven. The observatory and a town resident told The Associated Press that clashes had erupted between Israeli troops and residents when the Israeli troops fired.
The violence in the border area marks increased friction between Israel and Syria, where a new leadership has been installed after opposition factions ousted former leader Bashar al-Assad from power in December.
Israel says it will not tolerate an armed presence in southern Syria and has sent its troops into Syria's border zone. Syria's leadership has said it does not intend to open a front against Israel.
The Israeli military said militants in southern Syria opened fire toward Israeli troops, without specifying whether the Israeli troops were within Syrian territory when they were targeted.
It said its troops returned fire and that an Israeli warplane struck the militants. It gave no details on casualties but said "hits were identified".
Syria's foreign ministry said six people had been killed in the attack on Koya, a town in the southern province of Daraa, adding that the toll was expected to rise due to serious injuries sustained from the attack.
It has called for an international investigation into the Israeli attacks on its territory, describing them as a "blatant violation of its sovereignty".
Earlier, Israel said it had attacked two military bases, Tadmur and T4, in Homs province in central Syria.
Israel spent years carrying out airstrikes on Syria during Assad's rule, targeting Iran-linked military installations and weapons transfers from Tehran intended for the Lebanese armed group Hezbollah.
That arms route was cut when Assad was toppled but Israel has continued to carry out strikes on Syrian military bases.
The European Union's foreign policy chief Kaja Kallas warned on Tuesday that Israel's strikes into Syria "risk further escalation".
Speaking at a joint press conference with Israel's foreign minister Gideon Saar, Kallas said the pair had discussed Israel's actions.
"And we (the EU) feel that these things are unnecessary, because Syria is right now not attacking Israel," Kallas said.
The foreign ministry also urged Syrian people to reject any attempts to displace them or "enforce any new realities on the ground".