DUBAI, Oct 30: A suspected Al Qaeda parcel bomb found on a US-bound cargo jet was designed to blow up the plane, British premier David Cameron said on Saturday, as Yemeni authorities arrested a suspect in the plot.

The discovery of two packages containing explosives on aircraft in Dubai and Britain on Friday sparked an international security alert, with US officials saying the parcels were addressed to synagogues in Chicago.

But Mr Cameron told BBC television that after examination of the device found at East Midlands airport in central England, British authorities “believe that the device was designed to go off on the airplane.” US President Barack Obama has pointed the finger for the plot at Al Qaeda in the Arabian Peninsula (AQAP), the Yemen-based branch of Osama bin Laden's extremist network.

In Yemen, security forces arrested a woman “suspected of sending two parcel bombs,” after surrounding her house in the capital Sanaa, the defence ministry said.

President Ali Abdullah Saleh said his country was “determined to fight terror but would not allow anyone to intervene in its affairs.”

News of the arrest came shortly after Mr Cameron and Mr Obama's top counter-terrorism adviser both called Mr Saleh to urge his “close” counter-terrorism cooperation.

Mr Obama also called King Abdullah of Saudi Arabia. Riyadh had provided the tip-off for the discovery of the bombs.

In Dubai, police said the bomb found there contained the powerful high explosive PETN – the same substance used by would-be 2009 Christmas Day bomber Farouk Abdulmutallab and 2001 attempted shoe-bomber Richard Reid.

Dubai police chief General Dahi Khalfan said the device could have “exploded” on board the airplane had it not been intercepted in time.

The device consisted of a computer printer whose ink contained explosive material, connected to a mobile phone SIM card and a circuit board, a police statement said.

The parcel was flown in from Sanaa via Doha in Qatar on a Federal Express aircraft, an Emirati aviation official later said.

Yemeni authorities also announced the seizure of 26 other parcels on Saturday and said they were being examined.—AFP