The shockwave rattled windows, made birds fly up and was heard in every part of the city, leading to a surge in phone calls to police.
"Here are the coordinates to put in your Waze."
The vehicle exploded in the border town of Ras al Ain, which was taken by the Syrian rebels in 2019 from the Kurdish-led YPG militia. Two of those killed were children, residents said.
Security sources said the blast had caused a number of injuries.
Foreign claims of Israeli role validated; Physical sabotage, not cyber
Before the explosion, Lebanon was already grappling with its worst economic crisis in recent history, worsening poverty and decades of state corruption and mismanagement.
He also said the army inspected 143 containers at the port that he said were found to hold other flammable material.
There were no reports of casualties from the explosion which took place in a remote area early Friday, government spokesman Amjad Adailah told state media.