Hundreds of policemen have been posted to the area and closed it off with barbed wire.
Earlier this month, the authorities raided the mosque after a five-month stand-off with Islamic students, killing and arresting scores of people.
Since then, extremists have launched several attacks around Pakistan to avenge the mosque operation, killing more than 200 people, mostly policemen.
On July 27, a group of radicals temporarily took control of the mosque once again, but were later repelled.
(dpa)
