Updated

Al-Qaida in Yemen is vowing to avenge beheadings carried out by Saudi Arabia this week — an indication that some of the 37 Saudis executed on terrorism-related charges were members of the Sunni militant group.

Al-Qaida in the Arabian Peninsula, as the branch is called, posted a statement on militant-linked websites on Friday, accusing the kingdom of offering the blood of the "noble children of the nation just to appease America."

The statement says al-Qaida will "never forget about their blood and we will avenge them."

U.S. ally Saudi Arabia on Tuesday executed 37 suspects convicted on terrorism-related charges. Most were believed to be Shiites but at least one was believed to be a Sunni militant.

His body was pinned to a pole in public as a warning to others.