Islamabad (CNN) -- More than 100 Taliban fighters crossed over from Afghanistan and attacked three Pakistani military posts Sunday night, killing at least eight soldiers, Pakistani military officials said.
At least 15 Taliban fighters were killed in firefights that followed the attacks in the district of Upper Dir in northwest Paksitan, Colonel Wasim Ahmed told CNN.
Pakistani Taliban spokesman Ehsanullah Ehsan told CNN the Afghan Taliban carried out the attacks. The Pakistani Taliban helped with reconnaissance and information before the attack, Ehsan said.
Three other Pakistani military officials confirmed the attack but asked not to be named because they are not authorized to speak to the media on the record.
Sunday's attacks were the latest in a series of cross-border assaults from regions in eastern Afghanistan where U.S. troops began pulling out last year.
In 2011, cross-border attacks by militants killed scores of Pakistani soldiers and increased tensions between Pakistan and Afghanistan.
Kabul and Islamabad have long accused one another of not doing enough to secure the border.
Washington has almost always sided with Afghanistan in the finger-pointing, often blaming some of the deadliest attacks against western targets in Afghanistan on militants based in Pakistan's mostly ungoverned tribal region.
Journalist Aamir Iqbal contributed to this report.