Ayman al-Zawahiri has been appointed as al-Qaeda leader following the death of former leader Osama Bin Laden, BBC quoted a statement allegedly issued by the organisation's general command as saying.  

Ayman al-Zawahiri

Bin Laden was killed in a U.S. military operation in Islamabad in early May.

In his first video message since the death of bin Laden, al-Zawahiri warned that bin Laden would continue to "terrify" the US from beyond the grave, Wikipeadia said.