Video footage showed a fireball rising over the Lebanese capital overnight after another attack on the city.
According to a map provided by the Israeli military, there were reports that it may have struck a gas station.
Before the explosion, the Israeli military warned people in the southern suburbs to evacuate.
A BBC reporter at the scene heard six explosions and drones buzzing overhead.
The blast followed further Israeli attacks on the city, with Hezbollah also firing dozens of rockets into northern Israel on Saturday.
