The Turkish Defense Ministry, in a post published on its official Twitter page, said the attack took place in the city of Afrin, located more than 40 kilometers (24 miles) north of Aleppo, on Tuesday afternoon.
The ministry added that at least 40 people, including eleven children, were killed and 47 others wounded, blaming YPG militants for the explosion.
However, the so-called Syrian Observatory for Human Rights said at least 36 people were killed and nearly 40 others wounded when an explosive device inside the fuel truck went off at a market in the city.
The Britain-based war monitor said the blast left at least six Turkish-backed militants dead as well.
Back on October 31, 2019, a car bomb exploded in Afrin, leaving at least nine people dead and 30 others injured.
According to witnesses and a rescuer, the explosion took place at a busy market.
Some reports said at the time that two children were among the fatalities.
On July 11 that year, more than a dozen people, including eight civilians, were killed and several others sustained injuries when a car rigged with explosives went off in the same northwestern Syrian city.
The Observatory said then the car bomb exploded near a checkpoint, manned by Turkish-backed militants of the so-called Free Syrian Army (FSA), at the entrance to Afrin, where vehicles were gathering to be checked.
The UK-based group added that 13 people were killed in the explosion, which shook Tirende residential area south of Afrin center. More than 30 people sustained injuries as well.
In March 2018, the Turkish military and allied Syria militants took control of Afrin after a two-month-long offensive, which dislodged YPG militants from the Syrian city.