Found in Dubai bomb contained a powerful explosive substance

A US-bound package intercepted on a plane in Dubai contained explosives and bore the hallmarks of al-Qaida, Dubai police said today as international security services continued to investigate the terrorist threat.

The announcement came after security services in the UK and Dubai yesterday thwarted an alleged attempt to send explosive material hidden in printer ink cartridges by air from Yemen to strike targets in the US, The Guardian says.

President Barack Obama called the coordinated attacks a "credible terrorist threat." In Dubai, where one of the bombs was found in a FedEx shipment from Yemen, police said it contained PETN, a powerful industrial explosive, and bore the hallmarks of al-Qaida.

The white powder explosives were discovered in the ink cartridge of a computer printer, said a police statement carried by the official state news agency WAM.

The device was rigged to an electric circuit, and a mobile phone chip was hidden inside the printer, the statement said.

The police said the bomb was prepared in a "professional manner," according to The Associated Press.