Islamabad:
The US embassy in Islamabad on Thursday banned its staff from restaurants and markets in the Pakistani capital for several days either side of the anniversary of Osama bin Laden's death.
The Al-Qaeda kingpin was killed in a US special forces raid in the Pakistani garrison town of Abbottabad on May 2 last year and there are fears militants may mark the one-year anniversary with an attack.
"Due to security concerns, the US embassy has restricted its employees from going to restaurants and markets in Islamabad April 27 - May 5," a warning on the embassy website said.
"We recommend that US citizens in Islamabad during this period take similar precautions."
The 9/11 mastermind's three widows, their eight children and a grandchild are still being held in Islamabad after being detained in the Abbottabad raid.
They were originally supposed to be deported last week but the move was delayed because legal formalities were not complete.
A US official speaking on condition of anonymity said the warning was issued in response to information about a specific threat.
But Pakistan's deputy interior minister Imtiaz Safdar Warraich told Agence France Presse he had no information about a threat.