The Tehrik-e-Taliban Pakistan has claimed responsibility for two suicide bombings targeting Shia processions in Karachi and Lahore that claimed 16 lives on Tuesday.

Taliban spokesman Azam Tariq told reporters in the lawless North Waziristan tribal region on Wednesday that the two attacks on Tuesday were aimed against security personnel because "they serve the United States's interests".

"The security forces will face attacks as they protect US interests in Pakistan. The state of lawlessness is so bad that President Asif Ali Zardari has obtained the services of US-based security agency Blackwater," Tariq said while talking to the reporters on the phone from an undisclosed location.

"We will continue attacking the personnel of the security apparatus that are promoting US imperialism. They are creating hurdles for the soldiers of Islam. The personnel of the police and security forces are acting like the hirelings of the US and are destabilising Pakistan," he added.

Tariq claimed that Pakistan's top leadership "should keep in mind that they cannot protect themselves from Taliban attacks."

The country will be turned "into a citadel of Islam and secularism will be purged" from the land, he further claimed.

He also warned rights organisations to review their policies and stop promoting Western values.

"Only Islam guarantees human rights and stands for peace. A few secular families have turned Pakistan into their family fiefdom and are taking dictation from their Western masters. We have to rid Pakistan of these families," he said.

Sixteen people, including several policemen guarding the Shia processions, were killed and nearly 80 others injured in the two suicide attacks on Tuesday.