The Israeli military said it carried out a "targeted strike" in the Lebanese capital on Friday, while two security sources told Reuters the southern suburbs of Beirut had been hit.
Hezbollah's al-Manar TV reported "an attack" on the area.
"The IDF (Israel Defence Forces) conducted a targeted strike in Beirut. At this moment, there are no changes in the Home Front Command defensive guidelines," the Israeli military said, providing no further details.
A thick cloud of smoke could be seen rising over the capital, according to a Reuters live feed, after residents said they heard a loud blast.
