The Palestinian Islamist movement Hamas confirmed on Sunday that two of its members were killed when a bomb planted in a car exploded in Beirut's southern suburbs, a Hezbollah stronghold, dpa reported.
A Lebanese security source said one man was killed instantly in the blast, which took place late Saturday in Haret Hreik district, and the other died later at the hospital.
He added that at least five others were wounded and transferred to a hospital run by Hezbollah near Beirut International Airport.
Hamas spokesman in Beirut Ousama Hamdan was not available for comment, and the names of the dead were not released by the group.
Conflicting reports in Beirut said Hamas and Hezbollah members were trying to defuse the bomb when it exploded.
According to the Lebanese security source three bombs which were tied together were placed under a car in a parking lot near the Hamas office in Haret Hreik.
Local media reports said the Lebanese authorities were looking into whether intended victim may have been Ali Barakeh, the representative of Hamas in Lebanon.
Hamas - which runs the Gaza Strip - has offices in Beirut's southern suburbs, an area under the total control of the Lebanese Shiite movement Hezbollah.
The blast late Saturday came after Hezbollah chief Sheikh Hassan Nasrallah delivered a televised speech to mark the annual Shiite commemoration of Ashura, which marks the anniversary of the death of Imam Hussein, grandson of the Muslim prophet Muhammad at the Battle of Karbala in 680 AD.