In a disturbing development on Friday, Pakistan released Zakiur Rehman Lakhvi on bail. Lakhvi, who had been in Pakistani custody for the past six years, was the ringleader of the 2008 Mumbai terrorist attacks by Lashkar-e-Taiba (LeT). The U.S. had repeatedly urged the Pakistanis to move forward with the prosecution of Lakhvi, who allegedly directed the attacks that killed 166, including six Americans, but instead they have let him walk free.

The move follows on the heels of last week’s U.S. approval of the sale of nearly $1 billion in military equipment to Pakistan. The equipment, including attack helicopters and Hellfire missiles, is purportedly to fight terrorists on Pakistani territory.

Rebuff of the U.S.

Lakhvi’s release is a slap in the face of U.S. policymakers, who seek to support Pakistan in its fight against terrorists, despite continuing anger among the U.S. public and Members of Congress, who believe Pakistan secretly protected Osama bin Laden until the U.S. raid that killed him in May 2011.

His release will lead to outrage among the families of the victims of the Mumbai attacks. The families of the American victims have already filed petitions in U.S. courts seeking action against Pakistani officials who were allegedly involved in planning the Mumbai attacks. In October 2009, U.S. authorities in Chicago arrested David Headley, who later pleaded guilty in a U.S. court to involvement in the Mumbai attacks. In four days of testimony and cross-examination, Headley detailed meetings with a Pakistani intelligence officer, a former army major, and a navy frogman, who were among the key players in orchestrating the Mumbai assault.

International Condemnation

France and Israel have joined the U.S. in strongly condemning Lakhvi’s release. A U.S. State Department official expressed “grave concern” over Lakhvi’s release, stating that “terrorist attacks are an assault on the collective safety and security of all countries.” French President Francois Hollande expressed “indignation” over the release, while Israel’s Ambassador to the U.S. said it was a setback for the international fight against terrorism.

Unless Lakhvi is re-arrested by the Pakistani authorities, Members of the U.S. Congress may demand that arms sales to Pakistan be slowed or halted altogether. The U.S. may also consider putting a bounty on Lakhvi, as it has on LeT founder Hafez Muhammed Sayeed.

Pakistani Miscalculation?

Pakistani leaders seem to have miscalculated the level of international backlash against releasing Lakhvi. Since Pakistan has assisted the U.S. in targeting al-Qaeda terrorists, Pakistani military leaders may believe that they can continue to support terrorist groups that attack India, such as LeT, without incurring significant international costs.