Notwithstanding credible information that a terrorist attack was imminent and three suspicious bags found, airport officials let the 1985 Air India flight to take off from Toronto as they felt the cost of keeping the plane on the tarmac was too high.
Testifying before an inquiry into the bombing, baggage screener Daniel Lalonde said he overheard officials, whom he did not identify, saying that keeping the plane on the tarmac was too costly to justify searching baggage already on board, even though three suspicious bags had been found among those being loaded onto the plane.
"The cost of keeping the plane on the tarmac was high and the decision to let the plane depart was based on that factor," said Lalonde.
"The flight was going to go. The decision was that the plane was going to leave," Lalonde, who was 18 at the time, said describing a conversation between Air India security officers and airport personnel in testimony before the tribunal in Ottawa.
The revelation was the latest in a litany of security oversights, unheeded warnings and miscommunication among security officials in the days before Air India Flight 182 was blown from the sky, killing 329 people.
The lapses are a catalogue of missed opportunities: repeated warnings as early as 1984 and up to days before the disaster of attack by Sikh extremists; absent sniffer dogs at Toronto airport; a malfunctioning x-ray machine; a tardy policeman.
Most of those on board the ill-fated flight were Canadian citizens of Indian descent from Vancouver who arrived in Toronto on a connecting flight from a different airline.
After boarding Air India 182 in Toronto, they stopped over in Montreal, but never reached the next destination, London's Heathrow airport.
The bomb exploded in mid-air off the coast of Ireland on June 23, 1985. The same day, two Japanese baggage handlers died when a second bomb exploded in Tokyo's Narita airport in bags that originated in Vancouver and were destined to be placed on an Air India flight to Bangkok.
Justice John Major, who is chairing the inquiry into whether Canadian police did enough to avert the bombing, has stopped proceedings twice since it began in September over disputes with security officials over access to documents relating to the case.
Lalonde said that three bags, deemed suspect but later found to contain no explosives, were removed before they were placed on the plane in Toronto.
Earlier, the inquiry panel heard that Canadian officials were aware that Sikh extremists based in Canada were planning a terrorist attack on an Air India flight and that the security threat level had been raised.
Police alleged that the bombers were part of a militant cell of the Sikh separatist group Babbar Khalsa based in the Canadian province of British Columbia.
Only one person has been convicted for the bombing. In 1991, Inderjit Singh Reyat was sentenced to 10 years in a Canadian prison for supplying components for the bomb that exploded in Japan.
Ripudaman Singh Malik, a Sikh religious leader, and Ajaib Singh Bagri, a wealthy businessman, were acquitted after a sensational trial in 2005.
Lalonde's testimony came a day after the inquiry heard that the bomb-sniffing dog normally on site at Toronto's Pearson airport was away on a training exercise and unavailable to screen the luggage.
While normal security rules required that any suspicious luggage be hand-inspected, Royal Canadian Mounted Police officer Gary Carlson, the dog handler, confirmed this was not done.
In addition, an x-ray machine had malfunctioned, leaving baggage screeners with only hand-held wands, which had failed to detect explosives during a test six months earlier.
Earlier in the week, a policeman assigned to security at Montreal's Mirabel airport during the stopover testified that he arrived to check flight 182 only after the plane had departed for Heathrow.
The inquiry has also heard of a dispute between Transport Canada -- the federal transport agency -- and RCMP over who should bear the added costs of increased screening requested by Air India after the warnings.
Families of the victims have complained bitterly that they were not properly informed by Canadian officials as the crisis unfolded, and that the investigation was poorly handled by police.
