According to Reuters, this is the first attack within the Lebanese capital Beirut as Israel escalates hostility with Iran's allies in the region.
Reuters witnesses said the airstrike hit the upper floor of an apartment building in the Kola district of the Lebanese capital.
There has been no comment from the Israeli military yet.
The increasing frequency of Israeli attacks against Hezbollah militias in Lebanon and Houthi militias in Yemen has raised concerns that the war in the Middle East could spin out of control and draw in Iran and the United States.
The PFLP is another militant group involved in the war against Israel.
On September 29, Israel carried out airstrikes against Houthi militias in Yemen and dozens of Hezbollah targets across Lebanon after killing Hezbollah's leader earlier.
At least four people were killed and 29 wounded in air strikes on Yemen's Hodeidah port, which Israel said were in response to Houthi missile attacks.
In Lebanon, authorities reported that at least 105 people were killed in Israeli airstrikes on September 29.
More than 1,000 Lebanese have been killed and 6,000 injured in the past two weeks, according to Lebanon's Ministry of Health. One million people - one-fifth of the population - have been forced to flee their homes.
Two weeks of intense Israeli bombing have killed a number of senior Hezbollah officials, including leader Sayyed Hassan Nasrallah.
Israel has vowed to continue its attacks to ensure that northern areas are safe for residents forced to flee Hezbollah rocket attacks.
Israeli drones hovered over Beirut for most of September 29, with loud explosions from new airstrikes echoing across the Lebanese capital.
Many of the Israeli strikes were carried out in southern Lebanon, where Iran-backed Hezbollah conducts most of its operations, or in the southern suburbs of Beirut.
The September 30 attack on the Kola district appears to be the first within the city limits of Beirut.
The US has urged a diplomatic solution to the conflict in Lebanon but has also allowed its military to increase in the region.
Asked if a full-scale war in the Middle East could be avoided, US President Joe Biden replied, "It has to be avoided." Biden said he would discuss it with Israeli Prime Minister Benjamin Netanyahu.
