Pakistani security forces have detained at least 25 suspected Islamic militants in a series of raids linked to the July 7 London suicide bombings.
Officials in Punjab province say members of outlawed Islamist groups were among the people detained overnight in the cities of Dera Ghazi Khan, Multan, Faisalabad and Khushab.
They say the suspects are being questioned for possible links with three of the four London bombers - British-born Muslims of Pakistani origin who had visited Pakistan in the past year.
On Monday, Pakistani immigration officials released photographs of the three - Mohammad Sidique Khan, Shehzad Tanweer and Hasib Hussain - taken upon their arrival in Karachi.
There was no official confirmation of reports that at least one of the bombers visited Islamic religious schools during the visits.
Some information for this report provided by AP, Reuters and AFP.