reviewing its operations for later in the week . British Airways operates at least three flights a week to the Pakistani capital out of London 's Heathrow Airport . At a news conference in Islamabad on Sunday , Pakistani authorities released security video of the blast , showing a small explosion inside the truck before the larger , deadly explosion . Watch the truck bomb caught on tape In the video , a large truck crashes into the security gate , sending one security officer scurrying for safety . Then , as security guards approach the truck , the top of the vehicle explodes and the security guards flee . A small cloud of smoke appears above the truck , which is engulfed in flames minutes later . One of the security guards tries to put out the fire with a hand-held extinguisher , to no avail . The guards then walk away , and the camera freezes on the burning truck . Pakistani officials said the blast apparently disrupted electricity to the area , causing the closed-circuit television camera to malfunction . No arrests have been made in connection with the attack , Malik said Sunday , adding that
ISLAMABAD , Pakistan -LRB- CNN -RRB- -- More than 1,300 pounds of explosives were packed into a construction truck that detonated outside an Islamabad hotel , killing 57 people , including two Americans and a diplomat , officials said Sunday . A truck burns at the gate to the Marriott Hotel in Islamabad before a larger , deadly explosion Saturday . Pakistani Interior Minister Rehman Malik said the Saturday attack at the Marriott Hotel `` is the biggest attack , volume-wise '' in Pakistan in seven years . Two American military personnel who worked for the U.S. Embassy in Islamabad were among those killed , the U.S. military said . A Lithuanian and the Czech Republic 's ambassador to Pakistan , Ivo Zdarek , also were among the fatalities , police superintendent Sheikh Zubair said . The suicide truck blast injured 266 people , including 11 foreigners , according to Malik . Watch guards scatter after an explosion '' British Airways temporarily suspended its flights to Islamabad as a result of the security situation , according to an airline spokeswoman who did not want to be named . A Sunday night flight has been canceled , and the airline is