Little-known Modified Hellfire Likely Killed Al Qaeda's Zawahiri

Two Hellfire missiles fired from a drone killed the leader of al Qaeda, causing surprisingly little damage beyond the target, suggesting they may be a version shrouded in secrecy and used by the United States to avoid non-combatant casualties.

Officials said the missiles killed al Qaeda leader Ayman al-Zawahiri while he stood on a balcony at his home in downtown Kabul, Afghanistan, over the weekend in the biggest blow to the militants since Osama bin Laden was killed in 2011.

A senior administration official told reporters two Hellfire missiles were fired from an unmanned aerial vehicle at Zawahiri. U.S. officials said no one else was killed or wounded in the attack.

Hellfire missiles, mostly made by Lockheed Martin, are precision guided munitions for air-to-ground strikes that normally cause significant damage, taking down whole buildings and killing or severely injury anyone nearby.

Social media images of the strike pointed to the hallmarks of a modified Hellfire with six blades to damage targets and called the R9X, sources familiar with the weapon said. It is largely aimed at individual targets, such as militants in Syria.

The images showed windows destroyed on the second floor while the structure of the house remained intact despite being hit by Hellfires.

Officials believe the R9X is less likely to cause civilian casualties because instead of exploding, the missile cuts through targets with the sharp blades.

The MQ-9 Reaper, made by General Atomics, is the only drone that is publicly known to carry the Hellfire missile.

A Pentagon spokeswoman referred a query on the R9X missiles to U.S. Special Operations Command, which would be the prime purchaser of the missile.