Said al-Shihri, understood to be the second in command of Al Qaeda in the Arabian Peninsula, has been killed by defense forces in Yemen, according to reports of statements by Yemen's Ministry of Defense.

According to Reuters, the ministry's website displayed the news on Monday, saying that Shihri and six others had been killed by Yemen's army during what the ministry termed a "qualitative operation" in eastern Hadramout province.

CNN reported that officials in the Defense Ministry are in the process of confirming Said al-Shihri's identity with DNA tests.

Al Qaeda in the Arabian Peninsula, known as AQAP, "has been characterized by counterterrorism analysts as the most active and lethal Qaeda affiliate," according to the Council on Foreign Relations.

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Shihri's death would thus constitute "a deeply significant blow against AQAP," CNN Terrorism Analyst Paul Cruickshank said.

Shihri was held for years at the US's controversial Guantanamo Bay detention facility, though he was released in 2007, according to the BBC. The BBC also noted conflicting reports suggesting that Shihri may have been killed by a strike from a US drone.

BBC Arab Affairs Analyst Sebastian Usher noted that Yemen has previously reported the death of Said al-Shihri. "If confirmed it would be an important scalp for the Yemeni government in its US-backed campaign against Al-Qaeda," he said.