Abdelrahman, whose face and body was covered in gauze as he laid in Tripoli's al-Salam hospital, was one of those in line to get gasoline.
“There were hundreds gathered there, right next to the tank, and God only knows what happened to them,” he said.
The father of another casualty at the hospital said he had two other sons he still hadn't located.
The Red Cross said its teams were still searching the explosion site.
Angry residents in Akkar gathered at the site and set fire to two dump trucks, according to a Reuters witness.
Some of the injured were sent to hospitals in nearby Tripoli, while others were sent to Beirut, said Rashid Maqsood, an official with the Islamic Medical Association.
The majority of the injured are in serious condition, said Dr. Salah Ishaq of al-Salam Hospital. “We can't accommodate them, we don't have the capabilities. It's a very bad situation.”
With Lebanon deep in economic crisis, hospitals have warned that fuel shortages may force them to shut down in coming days, and have also reported low supplies of medicines and other essentials.
“The Akkar massacre is no different from the port massacre,” said former Prime Minister Saad al-Hariri on Twitter, referring to last year's massive explosion at the port in Beirut. He called on Lebanese officials including the president to take responsibility and resign.
Hariri is the leading Sunni Muslim politician, the dominant religion in Lebanon's north, and has been in open opposition to Lebanese President Michel Aoun.
Aoun expressed condolences, writing on Twitter that “this tragedy that befell our dear Akkar has made the hearts of all Lebanese bleed”. He added that he asked the judiciary to investigate the circumstances that led to the explosion.