The United States has evacuated all non-emergency staff from its consulate in Lahore, citing "specific threats" amid a worldwide alert over Al-Qaeda intercepts.
The US State Department also reiterated a longstanding warning to US citizens to avoid all non-essential travel to Pakistan, in a statement issued late Thursday Washington time.
The move came as Pakistan's troubled southwestern city of Quetta, focus of a surge in sectarian bloodshed, was hit by its second attack in two days as gunmen shot dead at least nine people outside a mosque on Friday.
The worshippers were gunned down as they left prayers for Eid al-Fitr, the festival marking the end of the Islamic holy month of Ramadan, which was marred in Pakistan this year by at least 11 attacks which killed 120 people.
A suicide bomber struck at a police funeral in the city on Thursday, killing 38 people in an attack claimed by the Taliban that will raise yet more concerns about the violence that has continued unabated since the newly-elected government took office.
The closure of the US consulate in Pakistan's second-largest city and cultural capital came amid heightened security measures in Islamabad, where police and soldiers were maintaining a highly visible presence on the streets.
"On August 8, 2013, the Department of State ordered the departure of non-emergency US government personnel from the US Consulate General in Lahore, Pakistan," the State Department statement said.
"The Department of State ordered this drawdown due to specific threats concerning the US Consulate in Lahore."
Meghan Gregoris, spokeswoman for the US embassy in Islamabad, said the evacuation was not linked to a terror threat that prompted the closure of 19 diplomatic missions in the Middle East and Africa.
"We received information regarding a threat to our consulate in Lahore. As a precautionary measure we have undertaken a drawdown for all but emergency personnel in Lahore," she told AFP.
The US embassy and consulates in Karachi and Peshawar were closed Friday for the Eid public holiday but are expected to open again on Monday, she said. The Lahore mission was likely to remain closed and there was currently "no indication" of when it might reopen.
"We will continue to evaluate threat reporting and take decisions as appropriate," she said.