TTP (Pakistani Taliban) normally fights against Pakistani government forces but now claims to have cooperated with Afghan Taliban during an attack inside Afghanistan.
Here their statement published online on 29-03-2013:
Tehrik-i-Taliban Pakistan – Statement No. 7
A Special Joint Operation by the Pakistani and Afghan Taliban against NATO Forces and the Afghan Army and Police
Praise be to Allah, the Lord of the Universe, and may prayers and peace be upon the Messenger of Allah, his family, his companions and his allies. Thereafter:
On March 5, 2013, the Pakistani and Afghan Taliban engaged in a special joint operation in the Giyan district in Paktia province in the Islamic Emirate of Afghanistan by attacking the joint military base for the NATO forces and the Afghan army and police.
The raid began when one of the sacrificing, martyrdom-seeking Afghan Mujahideen engaged in a martyrdom operation with a truck bomb on the military base.
Afterwards, more than 200 Mujahideen from the Tehrik-i-Taliban Pakistan attacked all the checkpoints and military posts surrounding the military base.
When the Mujahideen from the Tehrik-i-Taliban Pakistan attacked the military base, it had more than 200 soldiers from NATO and the Afghan army and police inside.
By the grace of Allah, the Mujahideen from the Tehrik-i-Taliban Pakistan successfully liberated all the checkpoints and military posts located at the military base.
In the operation, the Mujahideen obtained 2 LMGs, 2 RPGs, and 5 assault rifles.
The Afghan government broadcast admitted when it published the news of the operation that the attack killed 20 infidel and apostate soldiers. In reality, the losses were much greater than the number that was mentioned.
The Mujahideen captured three soldiers from the Afghan forces in this operation, and when the Mujahideen were returning, they killed them along the way and took their heads with them.
In this military operation, there were no human or financial losses for the Mujahideen. Only the Mujahid who engaged in a martyrdom operation with a truck bomb was martyred in this operation, and the praise and thanks belong to Allah.