A Pakistani court has ordered the release of the leader of an Islamic charity suspected of being a front for a group accused of the Mumbai attacks.
The court ruled the continued house arrest of Jamaat-ud-Dawa founder Hafiz Mohammad Saeed was unconstitutional.
The charity is accused of being a front for Lashkar-e-Taiba, the group India says was behind the attacks. Jamaat-ud-Dawa denies any links with militants.
India has expressed its disappointment, calling the release "regrettable".
More than 170 people died in the Mumbai (Bombay) attacks last November, including nine gunmen.
Mr Saeed, who is also a founder of Lashkar-e-Taiba, denies the charges against him. He was placed under house arrest in December after the UN added him to a list of people and groups linked to al-Qaeda or the Taliban.
Emerging from the Lahore High Court to shouts of support, Mr Saeed's lawyer, AK Dogar, said the court had ruled the house arrest was "against the law and constitution of the country".
The court also ordered the release of three other Jamaat-ud-Dawa members. A copy of the court order was not immediately available.
Pakistan's Attorney General Sardar Latif Khosa said the government would read the judgment before deciding whether to appeal against it.
India was swift to express its concern about Pakistan's commitment to fighting militancy following the court order.
"Pakistan has not shown the degree of seriousness and commitment it should have to bring to justice the perpetrators of the Mumbai attacks," Indian Home Minister Palaniappan Chidambaram told reporters.
More than 170 people died in the attacks in Mumbai in November
This is not the first time Mr Saeed has been placed under house arrest following militant attacks in India - only to be subsequently released.
The BBC's Chris Morris in Islamabad says the decision is likely to complicate efforts to improve relations between India and Pakistan.
But the US - which has listed Jamaat-ud-Dawa as a terrorist organisation - is also likely to be dismayed by the ruling, our correspondent adds.
A spokesman for Jamaat-ud-Dawa told the BBC the group had been confident that Mr Saeed would be vindicated.
HAFIZ SAEED IN CUSTODY
December 2001-March 2002: Arrested and released three times after Lashkar-e-Taiba was accused of attacking Indian parliament
August - October 2006: Detained after Lashkar-e-Taiba was linked to multiple train bombs in Mumbai
December 2008 - June 2009: Placed under house arrest after Lashkar-e-Taiba was blamed for Mumbai attacks
"We have nothing to do with militancy or militants," he said.
In an interview with the BBC just before being placed under house arrest in December, Mr Saeed denied any connection with the Mumbai attacks.
But the Indian authorities say there is evidence to show that they were planned and financed by Lashkar-e-Taiba in Pakistan.
Mr Saeed has been named on the official charge sheet in connection with the attacks.
Pakistan has admitted that they had been partly planned from its soil. The sole surviving suspected gunman is Pakistani and is currently on trial in Mumbai.
Founded in the late 1980s, Lashkar-e-Taiba is one of most feared groups fighting against Indian control in Kashmir.
After it was banned in Pakistan in 2002, the organisation divided itself into Jamaat-ud-Dawa and Lashkar-e-Taiba, correspondents say.
Jamaat-ud-Dawa works as an Islamic charity all over Pakistan.