Who planted the bombs?

Who planted the bombs?

Who planted the bombs?

Answers to your questions about the news.
July 7 2005 6:24 PM

Who Planted the Bombs?

How to verify a terrorist group's claim of responsibility.

Soon after this morning's bombings in London, several news sources found a message about the attacks on an Islamic militant Web site. In the statement, a group calling itself the "Secret Organization of al-Qaida in Europe" claimed responsibility for the acts of terrorism. Reports were careful to say that "the authenticity of the message could not be immediately confirmed." How do governments evaluate the veracity of such a claim?

First, they check the name of the group against a database of known terrorist organizations, then they evaluate the Web site where the claim was posted. It's likely that the group, the site, or both have been the source of past claims, and investigators keep track of which declarations turned out to be true. For example, a group of alumni from Abu Musab al-Zarqawi's Afghan training camp called Jund al-Sham has limited credibility after claiming credit for what turned out to be an accidental explosion at an oil refinery in Texas. If a claim of responsibility purportedly comes from an established terrorist organization, law enforcement officials will compare the posting's language and format to that used in known communications.

Daniel Engber Daniel Engber

Daniel Engber is a columnist for Slate.


Material evidence from the scene will be examined for corroboration. The kind of explosive device used in the attack, as well as the terrorists' timing and style, can be compared to previous events. Today's well-coordinated public transportation bombings in London recall last year's attacks in Madrid, which were claimed by "al-Qaida in Europe." The similarity in names and tactics suggests a connection, but experts are doubtful that the groups have close ties. Al-Qaida seems to be a loose network of independent groups that share a common ideology rather than a hierarchical organization.

Investigators will also monitor jihadist message boards for follow-up postings. After an Egyptian diplomat was kidnapped last Saturday, Zarqawi's group posted images of his identification cards a few days later. (Today, the group asserted that the diplomat had been executed. The Egyptian government has accepted the claim.)

The message boards often provide their own evaluations. In the next few days, Zarqawi and the leadership of other established al-Qaida groups may distance themselves from the London attacks. They could also send messages of congratulations and support. Zarqawi's spokesman, Abu Maysara al-Iraqi, has occasionally refuted faked messages attributed to his group. Alqal3ah, the site used for today's posting (and which has since gone offline), allows a large number of people to post. Spurious claims on lightly restricted message boards are not uncommon; a site administrator might even step in to chastise authors for false posts.

Evaluating terrorist claims was not always so complicated. In the 1970s, social revolutionary movements (like the Red Brigades in Italy) often made dramatic statements of responsibility with lengthy descriptions of their ideological goals. These were submitted directly to the press or to the authorities. The Irish Republican Army even worked out a code for communication with the British police to thwart potential copycats.

When America began using retaliatory strikes against state-sponsored terrorists in the 1980s, groups increasingly kept their bombings anonymous, perhaps by arrangement with the government that supported them. But as terrorism has become a more global problem, the pattern has reversed once again. That's probably because it's quick, easy, and safe to post a message on one of several thousand terrorist Web sites. Tracing the source of a message is very difficult without the cooperation of the site's administrator.

Explainer thanks Marvin Kalb and Louise Richardson of Harvard University, Oliver Lavery of PivX Solutions Inc., and Rebecca Givner-Forbes of the Terrorism Research Center.