Bomb was flown on passenger planes via Dubai & Qatar AirwaysOne of the two bombs posted from Yemen last week was transported on two passenger planes before being seized in Dubai, Qatar Airways says.
The device was carried on a Qatar Airbus A320 from Yemen's capital Sanaa to Doha, the company told the BBC.
There it was transferred onto another Qatar Airways aircraft to Dubai, where it was seized by police.
The bomb contained the explosive, PETN, which is difficult to detect using normal airport security screening.
A second device was found at East Midlands Airport in the UK. Both bombs were hidden inside printer toner cartridges.
Until now it had been thought that both devices had been transported using cargo planes.
The US freight firms, UPS and FedEx, had been used to post the devices, which were addressed to synagogues in the US city of Chicago.
The British authorities says the bomb seized in central England was believed to have been designed to go off in mid-air.
Qatar Airways was unable to confirm which type of passenger plane was used to fly the device on from Doha to Dubai, but said it would have been an A320, A321 or Boeing 777. The firm also runs one freight-only flight a week from Sanaa to Doha.
"Qatar Airways can confirm that a recent courier consignment was carried aboard one of its aircraft from Sanaa to Dubai, via Doha International Airport," said a statement on the airline's website.
"The carrier stated that, as per Chicago Convention, it is not the responsibility of the country in which the cargo transits to x-ray or inspect the cargo. This responsibility belongs to the country from where the consignment originates.
"Furthermore, the explosives discovered were of a sophisticated nature whereby they could not be detected by x-ray screening or trained sniffer dogs. The explosives were only discovered after an intelligence tip off."
Here is a link to Qatar Airways website
QATAR AIRWAYS STATEMENTDevice 1 intercepted at East Midlands Airport in the UK. It was posted via UPS in Yemen and is believed to have been flown via Dubai and Cologne
Device 2 intercepted in Dubai after flying on two Qatar Airways passenger jets from Yemen. It was posted via freight firm FedEx
Both devices are addressed to synagogues in Chicago, and contain PETN explosives stuffed into printer cartridges
Other UPS cargoes are searched in Newark, Philadelphia and New York as the alert spreads
The UK government later says it believes Device 1 was designed to go off on board the plane