Lebanon's Hezbollah movement announced on Tuesday it had chosen deputy head Naim Qassem to succeed Hasan Nasrallah as leader after he died in an Israeli strike in south Beirut last month.
Most of Hezbollah's top leadership has been killed in Israeli attacks since 23 September, when Israel dramatically escalated its war on Lebanon.
"Hezbollah's (governing) Shura Council agreed to elect... Sheikh Naim Qassem as secretary general of Hezbollah," the Iran-backed group said in a statement, more than a month after Nasrallah's killing.
Hashem Safieddine, the head of Hezbollah's executive council, was initially tipped to succeed Nasrallah.
But he too was killed in an Israeli strike on Beirut's southern suburbs shortly after Nasrallah's assassination.
Qassem, 71, was one of Hezbollah's founders in 1982 and was appointed the party's deputy secretary general in 1991, the year before Nasrallah took the helm.
He remained in this role after Nasrallah's predecessor, Abbas Moussawi, was assassinated by Israel in 1992.
He was born in Beirut in 1953 to a family from the village of Kfar Fila on the border with Israel.
He was the most senior Hezbollah official to continue making public appearances after Nasrallah largely went into hiding following the group's 2006 war with Israel.
In 2005, he wrote a history of Hezbollah which was seen as an "insider's look" into the group.
Since Nasrallah's death in a huge Israeli air strike on September 27, Qassem has made three televised addresses, speaking in more formal Arabic than the colloquial Lebanese favoured by Nasrallah, who is seen as a more charismatic figure.