AMERICAN INTELLIGENCE OFFICIALS intercepted suspect packages being sent from Yemen to Chicago in September, which may have been a ‘dry run’ for the bomb plot foiled last week.

The BBC reports the news from a US official that suspicious packages intercepted literature and other material, and that there were no explosives present, but that the packages were sent in order to ascertain how long they would take to arrive at each destination.

Intelligence sources believe that the packages were sent by a Yemeni militant group linked to al-Qaeda, who were also behind the two suspect packages intercepted last week by officers in the United Arab Emirates and the UK.

“We received information several weeks ago that potentially connected these packages to [Yemeni militant group] Aqap,” a senior official told PA on condition of anonymity. “They contained papers, books and other materials, but no explosives.

“When we learned of last week’s serious threat, we recalled the incident and factored it in to our government’s very prompt response.”

The two parcel bombs intercepted in Dubai and at the UK’s East Midlands airport last week – both addressed to Chicago-based synagogues – were packed with PETN explosives hidden inside printer toner cartridges.

Each of the two bombs was packed with about 300g of the explosive – 50 times more than would be needed to blast a hole in a metal plate twice as thick as the body of a cargo plane.

The two devices were reportedly ready to be activated using mobile phones, meaning that the ‘decoy runs’ sent in September could have been used by Aqap to ascertain the ‘best’ time to detonate the bombs in order to achieve maximum impact.

Germany has banned all direct flights to Yemen as a result of the security scare,