Al-Qaeda operatives in Libya may have mounted last week’s attack on the U.S. Consulate in Benghazi as revenge for the killing of Abu Yahya al-Libi in a drone attack in Pakistan in June.

The attack may have been encouraged by Abdul Wahab Al-Qaed al-Libi, the brother of the dead operative, according to a former U.S. intelligence officer who has contacts in the Libyan underground. Abdul Wahab was a member of the Libyan Islamic Fighting Group, a group linked to al-Qaeda that supposedly had entered politics after the toppling of Moammar Gaddafi last year.

U.S. intelligence agencies don’t have any evidence that Abdul Wahab personally helped plan the attack, according to an intelligence official. But the official said that the United States has received reports that the Sept. 11 attack in Benghazi may have been a reprisal for the June attack. “The idea of this being revenge for Abu Yahya’s death, we see discussion of that,” the official said. The attack killed J. Christopher Stevens, the U.S. ambassador to Libya, and three other Americans.

For al-Qaeda, Abu Yahya al-Libi was something of a rising star. When he was killed in the tribal areas of Pakistan on June 4, he was seen as one of the most skilled operations planners still alive among the inner core of al-Qaeda. He was about 49 when he died.

The Benghazi attack may be following the playbook of al-Qaeda leader Ayman al-Zawahiri, who since 2007 has been urging what he has called a “global intifada,” in which al-Qaeda would embrace and infiltrate jihadist movements. According to the former U.S. intelligence official, the talk in the Libyan underground last week was about what’s described as an “al-Qaeda intifada.”

The U.S. intelligence official confirmed that the United States has picked up chatter about this “intifada” strategy. “It’s something we’re looking at,” he said, but he wouldn’t discuss details and wouldn’t comment on any possible links with Zawahiri.

When Zawahiri become the leader of al-Qaeda after the death of Osama bin Laden in May 2011, U.S. analysts initially regarded it as a plus, from the American standpoint. That’s because Zawahiri’s opportunistic approach of hit-and-run attacks seemed less threatening to the United States than the preference of bin Laden and his closest associates for terrorist spectaculars on the order of 9/11. In that view, attacks like the one in Benghazi are tragic and deplorable, but the cost to America is lower than al-Qaeda operations targeted at the U.S. homeland.

The reports from the Libyan underground also said that a brother of Zawahiri had been seen among the crowds outside the U.S. embassy in Cairo last week. The U.S. intelligence official said that analysts couldn’t confirm that report, though he said that one U.S. agency has heard the same information.

An opportunistic al-Qaeda strategy, like that described by the Libyan source, would mean continuing attacks across the Arab world as the uprising once known as the “Arab Spring” continues. The Syrian revolution is especially vulnerable to being hijacked in this way by al-Qaeda. But it was evident during last week’s violent protests against an anti-Islamic video that there is dry tinder across the Muslim world, into which al-Qaeda is eager to toss a match.