The Syrian defence ministry said 36 people were killed and more than 50 wounded Wednesday in Israeli air strikes on the oasis city of Palmyra, renowned for its ancient ruins.
"The Israeli enemy launched an air attack from the direction of the Al-Tanf area, targeting a number of buildings in the city of Palmyra," a ministry statement said.
The attack "killed 36 people and wounded more than 50", as well as causing "significant material damage," it added.
The Syrian Observatory for Human Rights said the Israeli strikes killed 41 people, many of them pro-Iran fighters from neighbouring Iraq.
"Forty-one people have been killed, including seven pro-Iranian Syrian fighters and 22 non-Syrians, mostly Tehran-backed Iraqi members of the Al-Nujaba Brigades," the Britain-based war monitor said.
State news agency SANA said the Israeli strike "targeted residential buildings and the industrial area" of the city.
Since civil war erupted following a regime crackdown of pro-democracy protests in 2011, Israel has carried out hundreds of strikes in Syria, mainly targeting the army and Iran-backed groups.
The Israeli military has intensified its strikes since almost a year of hostilities with Hezbollah in neighbouring Lebanon escalated into all-out war in late September.
Israel rarely comments on individual strikes in Syria but has repeatedly said it will not allow Iran to expand its presence in the country.