Police and security officials survey the site of a bomb blast in Peshawar, May 20, 2011.
Source: Press TV
Pakistani security forces have barred at least 10 American diplomats from entering the troubled northwestern city of Peshawar.
Security forces banned entry to four diplomats on Tuesday and six others on Wednesday and sent them back to Islamabad.
Pakistani officials say the diplomats were refused entry for not having No-Objection Certificates (NOCs) -- the legal permission foreigners need to have to enter Peshawar.
"No foreigner is allowed to enter Peshawar without prior permission from the authorities concerned and we have informed the US citizens to carry No-Objection Certificates (NOCs) while coming to Peshawar or else they won't be allowed entry," the provincial senior minister Bashir Bilour told a news conference in Peshawar.
"Pakistan is a sovereign country and no foreigner is above the law," he added.
The US embassy in Pakistan has expressed concern over the incident, saying it will look into the issue.
Tensions between the two countries increased following a secret US raid on Pakistan in May that allegedly killed al-Qaeda leader Osama bin Laden.
Some White House officials suggest that Islamabad was aware of bin Laden's location.
Washington-Islamabad relations have already strained over a surge in unauthorized US drone attacks in Pakistan and NATO operations along the border in which hundreds of civilians have been killed.