ISLAMABAD, Pakistan - A Pakistani court on Friday ordered the release of the main suspect in the 2008 Mumbai terror attacks by canceling a government order under which he was detained for the last three months, a defense lawyer and prosecution said.

But Zaki-ur-Rahman Lakhvi was unlikely to be freed quickly because he still faced charges in a separate kidnapping case, prosecutor Jahangir Jadoon said. The Islamabad High Court "canceled the detention order for Lakhvi after concluding that no solid evidence was available to keep him in the jail," he said.

Defense lawyer Rizwan Abbasi said his client had been implicated in that kidnapping case in December to block his release. Another court already granted bail in that case, and the government has no authority to keep Lakhvi in jail, the lawyer said.

"The government may show rigidity, and it may use delaying tactics in releasing Lakhvi to appease India," Abbasi said.

Lakhvi is one of seven people being tried by Pakistan in connection with the attacks, which killed 166 people and seriously damaged relations between Pakistan and India. India has repeatedly urged Pakistan to actively pursue the case against Lakhvi, who was accused of planning the attack, and other suspects.

India's Ministry of External Affairs summoned the Pakistani high commissioner in New Delhi on Friday and conveyed India's disappointment at the court's ruling.

India's junior home minister, Kiren Rijiju, said Islamabad had not produced clinching testimony against Lakhvi despite possessing sufficient evidence.

Abbasi said his client has been in government custody since 2009. Lakhvi has remained jailed under a special detention order even though a court granted bail in December in the Mumbai case.

U.S. State Department spokeswoman Jen Psaki told reporters Friday in Washington that the American government was closely monitoring developments in the Lakhvi case. "The government of Pakistan has pledged its cooperation in bringing the perpetrators, financiers, and sponsors of the Mumbai terror attacks to justice and we urge Pakistan to follow through on that commitment," Psaki said.

Also Friday, Pakistani warplanes pounded militant hideouts in a northwestern tribal region near the Afghan border, killing at least 48 suspected militants, the military said.

In addition, the military said Friday that it has successfully tested its first armed drone and will begin using the weapons against terrorists operating inside the country's borders.