A court in the Pakistani province of Punjab has acquitted two men charged in connection with a suicide bomb attack on a Shia mosque in Sialkot.
Shia mosques have often been targeted in sectarian violence
At least 30 people died in the attack on 2 October 2004, and dozens of others were injured.
The anti-terrorism court said that the prosecution had failed to provide conclusive proof against the two.
A defence lawyer told the BBC that the original police report mentioned only one person as being involved.
That person was the alleged bomber who is believed to have died when he joined the Shia prayer meeting and detonated a bomb inside an attaché case.
The BBC's Shahid Malik in Lahore says that the two people acquitted were implicated by police at a later stage.
They were arrested near the southern city of Multan a few months ago on charges of aiding and abetting the attack.
But prosecution witnesses at the anti-terrorism court - sitting inside the central jail in Gujranwala for security reasons - were not able to establish a link between the pair and the suicide bomber, defence lawyer Asghar Rokari said.
"We had applied to the court to quash the charges against the two, and our plea has been upheld," he said.