Al-Qaida's number two Ayman al-Zawahiri has issued a new video message praising the terrorist organization's slain commander in Afghanistan, the IntelCenter, a US group that monitors militant messages, said Wednesday. The nine minute, 59 seconds-long tape, entitled "An Elegy to the Martyred Commander Abu Laith al-Libi," was issued by al-Sahab, the organization's media branch. The video has English subtitles, IntelCenter said. Its authenticity could not be immediately verified. Libi is believed to have been killed by a missile from a US Predator drone that struck his safehouse in Pakistan in late January. He was viewed as a top al-Qaida strategist in neighboring Afghanistan.