The report "As If Hell Fell on Me" says more than 1,300 civilians were killed in fighting between Pakistani troops and Taleban in 2009 while more than one million displaced people are still in various towns.

"Over the last few years, Taleban have been able to assert their rule, their ideology through combination of violence and fear," Saman Zia-Zarifi, director Asia-Pacific, told reporters in Islamabad.

"They have killed anybody who can challenge them. They have killed hundreds of maliks (tribal elders), religious leaders, civil society workers, teachers."

He said militants also used the civilian population as human shield against military assaults and often placed themselves in residential areas.

Pakistan went on an offensive last year to crush Al-Qaeda-linked Pakistani militants who wanted to impose Taleban-style strict Islamic rule in their strongholds in northwestern Swat and the tribal areas.

In their violent campaign, militants killed thousands of people in the country.

The military say the tribal lands have largely been cleared of militants in these operations.

Zarifi accused government forces of not trying to protect civilian population in the conflict-zones and using indiscriminate artillery and air power against them.

"The government acted as if its role is simply to kill the enemy as if it was not there to protect the citizens of Pakistan," he said.

"The Pakistani military is not designed to fight counter-insurgency. It's not designed to provide the rule of law. It's really designed to fight a mechanized war probably against India but that's not the situation in FATA and neighboring areas."

The international human rights watchdog's report says some 2,500 people are said to have been detained by Pakistani authorities without framing any charge against them. It fears the figures of enforced disappearance could be much higher.

"It does no good for justice to simply detain these people in secret places and have them show up dead in encounter killings," Zarifi said asking the government to try them in the courts.

The report also criticizes the role of "unaccountable and untrained" tribal militia raised with the backing of authorities against Taleban.

"In some they seem to say they target Taleban but other cases they're simply carrying old vendetta or taking advantage of the situation to settle scores," the Amnesty official said.

"It's the opposite of enforcing the rule of the law. This is moving toward chaos."