"An enemy raid targeted, just now, (Beirut's) southern suburbs," the National News Agency (NNA) reported.
AFP correspondents heard two loud explosions and saw smoke rising from the southern suburbs.
A source close to the group told AFP that the earlier strikes had "targeted a building housing Hezbollah's media relations office", which had already been "evacuated".
This week, Israel announced that its troops had started "ground raids" into parts of southern Lebanon, after days of heavy bombardment of Hezbollah strongholds around the country.
After nearly a year of low-intensity cross-border fighting, Israel has shifted the focus of its operation from Gaza to Lebanon, where heavy bombing has killed more than 1,000 people and forced hundreds of thousands to flee.
Last week, Israel killed Hezbollah leader Hassan Nasrallah in south Beirut, a densely populated area before residents fled Israel's intensifying bombardment.