Syrian outlet Sham FM reported Thursday that at least 18 Syrian soldiers were killed and more than 20 were wounded when an explosive device detonated on a military bus in the Damascus countryside.

"At least 18 soldiers were killed after an explosive device went off in a military bus in the province of Damascus," a security source also confirmed to Sputnik, while a military source told SANA that the attack left 27 injured.

Reuters said that "there was no immediate claim of responsibility for Thursday's attack," which represents one of the deadliest attacks in months against Syrian soldiers.

It is noteworthy that in mid-May, an attack by extremists in the Aleppo countryside left 12 Syrian army soldiers martyred and injured 14 others, and in early March, the Syrian Defense Ministry reported that 13 Syrian soldiers were martyred and another 18 injured in a terrorist attack that targeted a bus in Tadmor.

In addition, SANA reported in January that five Syrian soldiers were martyred and dozens were injured in an ISIS attack in the Syrian desert.

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