The cargo plane bombs were more than capable of blowing a hole in an aircraft fuselage, officials have said.

Experts in Germany said the bombs at East Midlands Airport and in Dubai contained at least 300g of the powerful explosive PETN as Home Secretary Theresa May announced a review of all air freight security.

UK explosives expert Sidney Alford told CNN last year that just 6g of PETN would be enough to punch a hole into a metal plate twice the thickness of an aircraft fuselage.

Mrs May told MPs both bombs originated in Yemen and were believed to be the work of al-Qaeda in the Arabian Peninsula.

She said: "The devices were probably intended to detonate mid-air and to destroy the cargo aircraft on which they were being transported. Had the device detonated we assess it could have succeeded in bringing down the aircraft."

Announcing a security review, she said all flights containing unaccompanied freight from Somalia will be suspended in the wake of the terror plot.

Ink cartridges larger than 500g will also be banned from hand baggage on flights departing from the UK and also on cargo flights unless they originate from a regular shipper with security arrangements approved by the Department for Transport, Mrs May said.

The bomb at East Midlands Airport was removed from a UPS aircraft by Leicestershire police officers shortly after 3.30am on Friday following a tip-off from Saudi intelligence. It had travelled through a UPS hub at Germany's Cologne airport before being detected in the UK following the tip-off, officials said.

Yemeni security officials said the tip-off came from a leading al-Qaeda militant who turned himself in to Saudi authorities last month. Jabir al-Fayfi told authorities about the plan by Aqap, the terror group's affiliate in Yemen.

Qatar Airlines confirmed on Sunday the parcel bomb discovered in Dubai was transported on two separate passenger jets before being found by security staff.

Norman Shanks, former head of security at airport operator BAA, said it was time to introduce "package by package" screening after it emerged one of the cargo plane bombs was transported on passenger aircraft before being found.