At least 2,500 people have been killed as a result of U.S. drone and Taliban attacks in Pakistan since January 2009, a local newspaper Daily Times quoted a research report as saying on Saturday.

According to the report, the U.S. drone attacks in the tribal areas of northwest Pakistan, which border Afghanistan, have been increased by three times under the President Barack Obama administration.

The number of drone attacks rose to 88 times during the 18 months of the President Obama's tenure from January 20, 2009 to the end-June 2010 as compared with the 25 drone strikes between January 2008 and January 2009, said the report, adding over 700 people have been killed in the US drone strikes in the afore-said period.

Meanwhile, the Taliban militants have also stepped up their retaliation by launching more than 140 attacks in various locations across Pakistan since the beginning of 2009, killing over 1,700 people and injuring hundreds more, said the report.

While the attacks by the Taliban militants cannot be described as direct retaliations for the US drone strikes, they are definitely part of the actions taken by the militants in response to the operations launched by the U.S. drones and the Pakistani army against their bases in northwest Pakistan.

The increase in the number of strikes by the U.S. drones is partially due to the shift of the US police to extend its military operations from targeting al-Qaeda militants to the militants of Tehreek-e-Taliban Pakistan, said local analysts.

Most of the drone strikes were carried out in the country's northwest tribal areas of South Waziristan and North Waziristan, two strongholds of the militants in Pakistan.

Early Saturday morning, a U.S. drone fired five missiles at a suspected militant hideout in South Waziristan, killing at least 16 people and injuring many others.

The U.S. drone strikes are considered as a serious violation of Pakistan's territorial air space right and they are an important factor contributing to the anti-American sentiment prevailing among the local people as most of the killed and injured in the drone attacks are reportedly innocent civilians.