Only one of the 5,000 terrorist attacks in 2011 is attributed to Al-Qaeda Central, but more than half of the top 20 most active perpetrator groups in 2011 are linked to Al-Qaeda, according to new data released in the National Consortium for the Study of Terrorism and Responses to Terrorism (START) Global Terrorism Database (GTD), based at the University of Maryland.

The most comprehensive, unclassified database of terrorist incidents, the GTD now contains information on more than 1,04,000 domestic and international terrorist attacks between 1970 and 2011 that resulted in more than 2,25,000 deaths and more than 2,99,000 injuries. These attacks are defined as the threatened or actual use of illegal force and violence by a non-state actor to attain a political, economic, religious or social goal through fear, coercion or intimidation.

The top five most active perpetrator-groups of terrorist attacks in 2011 were: Communist Party of India-Maoist (CPI-M); Taliban; al-Shabaab; Boko Haram; and Revolutionary Armed Forces of Colombia (FARC).

While only one of the attacks in 2011 was attributed to Al-Qaeda Central—the August kidnapping of Maryland native Warren Weinstein in Pakistan—11 of the top 20 most active groups are linked to Al-Qaeda. Those groups alone carried out more than 780 attacks that resulted in more than 3,000 deaths and wounded 4,600.

Al-Qaeda-linked groups were responsible for four of the top five most lethal attacks in 2011. The attacks were Al-Qaeda in the Arabian Peninsula (AQAP), Yemen (March 28): 110 killed, 45 injured; Tehrik-i-Taliban Pakistan (TTP), Pakistan (May 13): 80 killed, 140 injured; al-Shabaab, Somalia (October 4): 70 killed, 42 injured; and Al-Qaeda in Iraq, Iraq (March 29): 65 killed, 95 injured.

“Total attacks in the GTD in 2011 continued an upward trajectory that began a decade ago, paced by the ongoing historic shift in attacks away from Al-Qaeda Central and toward its growing number of affiliates,” said Gary LaFree, START Director and Professor of Criminology and Criminal Justice at the University of Maryland.

The other most lethal terrorist attack in 2011 was committed July 22 by Anders Breivik in Norway. He killed 69 people and injured at least 60 others when he opened fire on a youth camp hosted by Norway’s ruling Labor Party. Additionally, earlier that day, he detonated explosives in an attack that killed eight people and injured at least 15 others. Breivik confessed to the attacks and in August 2012, was sentenced to 21 years in prison.

Terrorist attacks in just five countries accounted for 70 per cent of the terrorist attacks worldwide in 2011: Iraq (25.78 per cent); Pakistan (19.96 per cent); India (12.67 per cent); Afghanistan (8.35 per cent); and Russia (3.71 per cent).

With the release of the 2011 data, for the first time, the START Consortium also released four decades of geocoded GTD data for eight regions of the world. The geocoding allows researchers to chart the city-level progression of attacks across global regions and specific terrorist groups and movements, including: the spread of leftist violence in Europe in the 1970s; the diffusion of terrorism in Central American conflicts during the 1980s; the prevalence of ecoterrorism in the United States during the 1990s; and the contagion of terrorism in the Caucasus region during the 2000s.

“The advent of satellite technology and geographic information systems is revolutionising the study of crime, political violence and terrorism,” LaFree said. “By releasing geocoded GTD data for the first time, we are making a down payment on what we hope will eventually be a fully geocoded Global Terrorism Database.”

Top 20 most active groups in 2011

The following are the top 20 most active groups: Communist Party of India-Maoist (CPI-M); Taliban; al-Shabaab; Boko Haram; Revolutionary Armed Forces of Colombia (FARC); Tehrik-i-Taliban Pakistan (TTP); Al-Qaeda in the Arabian Peninsula (AQAP); New People’s Army (NPA); Kurdistan Workers’ Party (PKK); Baloch Republican Army (BRA); Al-Qaeda in Iraq; Garo National Liberation Army; Al-Qaeda in the Lands of the Islamic Maghreb (AQLIM); Lashkar-e-Islam (Pakistan); Abu Sayyaf Group (ASG); Islamic State of Iraq (ISI); People’s Liberation Front of India; Haqqani Network; Lord’s Resistance Army (LRA); Lashkar-e-Jhangvi; and Al-Qaeda-linked group.