India summoned Pakistan High Commissioner Abdul Basit on Friday and lodged a strong protest against a court in Islamabad ordering the release of Mumbai attack mastermind Zakiur Rehman Lakhvi, official sources said.
Basit, however, refused to speak to the media after the meeting ended.
The Islamabad High Court on Friday declared Lakhvi's detention orders illegal and ordered his immediate release.
Lakhvi, along with six other suspects, was in detention since February 2009.
He is accused of being the mastermind of the Mumbai terror attack in November 2008 in which 166 people, including foreigners, were killed and hundreds of others were wounded.