Parcel bombs: The case of exploding letters

Recent terrorist attempts using parcel bombs raise concerns of inadequate screening measures in Pakistan.

ISLAMABAD: A recent wave of attempted parcel bombings in Europe and United States has invoked fresh fears that the phenomenon might gain traction in regions already plagued with terrorism, including Afghanistan and Pakistan where al Qaeda presence is an established fact.

“A parcel bomb is the best technique to take out an individual high-value target,” said an official of the bomb disposal squad of Islamabad Police.

Experts believe the parcel bombs can be easily detected, provided an effective detection mechanism is in place at ports, post offices, courier services offices and, most importantly, at sensitive installations.

Officials in the postal services and customs fear that Pakistan, due to the lack of such mechanisms, is extremely vulnerable to terrorist attacks by parcel bombs.

“If there is a threat from a parcel bomb it would most likely come from within the country since terrorist outfits based in our tribal belt are very much capable of acquiring such bombs and using them,” said Amir Rana, an expert on counter-terrorism.

The seriousness of the issue moved the Special Branch of the Islamabad Police to prepare a descriptive report about letter or parcel bombs for security agencies, police and those responsible for VIP security.

The report stated that “a parcel bomb is an explosive device sent via postal service, designed to kill or injure the recipient on opening it”. The phenomenon is as old as 1950s and has been used effectively by terrorists to kill important personalities across the world, it added.

What makes a parcel bomb deadly is the use of pentacrithritol trinitrate (PETN), a highly potent explosive which is difficult to detect in security screenings. PETN has a very low vapour pressure, which means very little of it gets into the air and hence, cannot be easily detected. This property makes PETN one of the most effective weapons in the hands of terrorists.

Recently at least one of the packages sent to US from Yemen contained PETN. The package was traced back to Al-Qaeda’s Saudi and Yemen branches, which merged in January 2009.

“One gram of PETN is sufficient to kill the recipient,” said Major Tabassum, incharge of Islamabad Police’s bomb disposal squad. What’s worrisome is that about eight to 10 grams of PETN can be packed in a normal-sized parcel, he added.

While a parcel bomb can be detected through a visual scanner, such as those at ports, it is not very practical to implement everywhere. “Visually scanning all parcels for detecting explosives at ports and post offices is not be humanly possible,” said Ashar Azeem, a customs official.

“I think we should have particle analyzers fixed at ports and our post offices,” he added.

The particles analyze, already being used by security agencies for detecting explosives, is one possible solution to the problem as it can detect explosives without human input. “It is like a sniffer dog but with a very sharp nose,” said Azeem.

However such a machine is only available at a few five-star hotels and sensitive government installations in the capital.

The lack of preparation makes terrorist attacks using parcel bombs a disaster waiting to happen.

“Terrorists are aware of this technique. Letters was used to disseminate anthrax in Karachi in 2003-4,” Rana, the expert, said. He added, “No parcel bombs have so far been used in Pakistan probably because the suicide bombings have not been much of a problem for them so far.”

While terrorists have not yet used parcel bombs, Rana said that the improving security measures at sensitive locations might force terrorists to reconsider their tactics. And, he said, proper precautions are needed to prepare for such an eventuality.

Published in The Express Tribune, November 13^th, 2010.