Islamabad: Pakistani officials on Tuesday accused the Afghan army of firing mortar bombs across the border, killing four Pakistani soldiers and stepping up a recent surge of cross-border violence.
The officials said two other soldiers were wounded in the attack in South Waziristan, part of the lawless tribal district on Pakistan`s border with Afghanistan that Washington has called the global headquarters of Al-Qaeda.
Afghan officials were not immediately reachable for comment. The deaths came with Afghan President Hamid Karzai due to host his Pakistani counterpart Asif Ali Zardari in Kabul on Tuesday.
"Four soldiers were killed and two others were wounded in this cross-border attack," a security official in Pakistan`s northwestern city of Peshawar told AFP, saying that the shelling continued for around two hours.
"More than 20 mortar shells were fired from across the border. Three shells slammed into a paramilitary Frontier Corps checkpost in Angoor Adda," he added.
Another security official in Wana, the main town in South Waziristan, confirmed the incident and casualties.
Both officials blamed the Afghan army for the attack.
In recent weeks tensions have sharply risen on the border between Pakistan and Afghanistan`s Kunar and Nangarhar provinces, which villagers say have been bombarded with hundreds of rocket attacks.
Hundreds of Afghans took to the streets in the eastern town of Jalalabad last week chanting "death to Pakistani invaders" to protest against cross-border attacks that they claim have killed dozens of people.
Pakistan says its security forces may have fired a few accidental rounds into Afghanistan while pursuing militants. It also says that insurgents from Afghanistan have crossed the border to attack security checkpoints.
Taliban and other Al-Qaeda-linked militants have carved out strongholds on both sides of the porous border. Afghanistan and Pakistan blame each other for cross border attacks and responsibility for militant sanctuaries.
Pakistan`s president was in Afghanistan on Tuesday following talks in Iran, where President Mahmoud Ahmadinejad called for a boost in relations.
Karzai`s office said Zardari had come to pay his respects over last week`s assassination of the president`s brother, Ahmed Wali Karzai, known as the "king of Kandahar" and the key powerbroker in southern Afghanistan.
But the visit also comes with Pakistan keen to be included in Afghan and US efforts to reach out to the Taliban and broker a political solution to 10 years of fighting in Afghanistan.