An adviser to the health ministry said the death toll from the blast in Al-Tleil village, in the Akkar region, had climbed to 28. The Lebanese Red Cross said 79 others were injured.
The military said a fuel tank that "had been confiscated by the army to distribute to citizens" exploded just before 2:00 am (2300 GMT). Soldiers were among those hurt.
The army began raiding gas stations Saturday to curb hoarding by suppliers following a central bank decision to scrap fuel subsidies.
The official National News Agency (NNA) said the blast followed scuffles between "residents that gathered around the container to fill up gasoline" overnight.
Hospitals in Akkar, one of Lebanon's poorest regions near the border with Syria, and in the northern port city of Tripoli said they had to turn away many of the injured because they were ill-equipped to treat severe burns.
"The corpses are so charred that we can't identify them," said Yassine Metlej, an employee at a Akkar hospital where seven bodies and dozens of injured were brought.