At least 30 people were killed and over 50 others injured when a huge blast ripped through a mosque in northwest Pakistan Friday afternoon, reported local Urdu TV channel Express. According to the local media reports, the blast took place at about 2:00 a.m. local time Friday in a mosque at the Ghondi area of Jamrud, a district in Pakistan\'s northwest tribal area of Khyber Agency which borders Afghanistan. Hundreds of people were offering Friday prayers inside the mosque when the explosion occurred, said local media reports. Some reports said over 100 people were inside the mosque hit by the blast while others put the number at 500 to 700 people. The entire building of the mosque collapsed following the blast, according to the reports. Local TV channel Geo quoted eyewitnesses said that the blast was a planted bomb attack, but the report is not officially confirmed.