Syria: Death toll 'rises to 68' after suspected Islamic State attack
"A total of 61 civilians and seven soldiers have been killed in the attack," said Rami Abdurrahman, who heads the Syrian Observatory for Human Rights.
The UK-based Observatory, which has a network of sources inside Syria, said the attack had been carried out on Friday by suspects on motorcycles who opened fire on truffle hunters.
The monitor said that IS was taking advantage of the annual harvest of the desert fungus delicacy, which generally runs from February to April, to carry out attacks in remote locations.
The attack takes the total number murdered in suspected IS attacks in the Syrian desert to 90 since 10 February, the monitor said.
IS group did not immediately claim the attack on its channels.
Syrian state media reported 53 deaths on Friday, after the attack southwest of the town of Al-Sokhna, in the desert east of Homs.
It was the deadliest attack by IS since January last year, when they stormed a prison in the Kurdish-controlled northeastern city of Hasakeh in a bid to free fellow members.
The resulting fighting inside the city killed 105 people, mostly civilians, as well as 268 fighters.
After IS lost their last scraps of territory following a military onslaught backed by a US-led coalition in March 2019, remnants of the group in Syria mostly retreated to hideouts in the desert.
They have since used such hideouts to ambush Kurdish-led forces and Syrian government troops while continuing to mount attacks in neighbouring Iraq.
Separately on Friday, the US Central Command said four American military personnel were injured in a blast during a raid that killed a senior IS leader in Syria.
The IS leader, identified as Hamza al-Homsi, was killed, while the US troops and a working dog were being treated at an American medical facility in Iraq, it added.