WASHINGTON - In the past five years, terrorist attacks have killed nearly 20,000 people across Africa. Two groups, Boko Haram and al-Shabab, accounted for 71 percent of reported incidents and 91 percent of fatalities.

But, while these and other militant groups remain active, fatal terrorist attacks across the continent are on pace to fall for a second straight year, and the total number of attacks is running far below 2012 highs.

These findings are part of VOA’s original analysis of data from ACLED, the Armed Conflict Location and Event Data Project. ACLED tracks political violence, protests and terrorist events across Africa. Their reports include attacks since 1997 based on data collected from local news media, government statements, non-governmental organizations and published research.

Terrorism Deaths: Terrorist Groups That Have Launc Terrorism Deaths: Terrorist Groups That Have Launched the Most Attacks in Africa Since 2013 Terrorism Deaths: Terrorist Groups That Have Launched the Most Attacks in Africa Since 2013

Review of incidents

To conduct its review, VOA analyzed a portion of the full ACLED dataset by comparing the primary perpetrator of each attack to a list of 34 terrorist organizations. Those groups are named on the U.S. State Department’s Foreign Terrorist Organizations and Terrorist Exclusion lists, or in a separate analysis conducted by the Africa Center for Strategic Studies. All known aliases were included, accounting for more than 100 group names.

Since ACLED doesn’t identify terrorist attacks or groups, this step was necessary to remove other kinds of violence from the analysis.

Terrorism Deaths: Terrorist Groups That Have Cause Terrorism Deaths: Terrorist Groups That Have Caused the Most Deaths in Africa Since 2013 Terrorism Deaths: Terrorist Groups That Have Caused the Most Deaths in Africa Since 2013

According to the data, the number of terrorism deaths in Africa reached an all-time high in 2015, when Boko Haram killed more than 8,000 people across Nigeria, Cameroon, Chad and Niger.

No group has inflicted more death and destruction on the continent than Boko Haram, which has accounted for one-third of terrorism deaths in Africa in the past 20 years.

Terrorism Deaths: African Countries with the Most Terrorism Deaths: African Countries with the Most Deaths Since 2013 Terrorism Deaths: African Countries with the Most Deaths Since 2013

Since 2015, the number of terrorism deaths has dropped, in no small part because of military campaigns to weaken the radical Islamist group carried out by the Nigerian army and a multinational task force.

In 2016, the fewest number of terrorism-related deaths in nine years was recorded, and 2017 is on pace to continue that trend, with 893 deaths reported as of June 24.

Attacks peaked in 2012

The number of terrorist attacks peaked in 2012, not only because of Boko Haram and al-Shabab, but also because of militant groups in Mali, where al-Qaida in the Islamic Maghreb and allied groups briefly took control of the north.

Since then, attacks have gradually declined. However, if current trends hold, overall attacks in 2017 will pass last year’s total, but will still fall far short of the 2012 high.

Terrorism Deaths: African Countries with the Most Terrorism Deaths: African Countries with the Most Terrorist Attacks Since 2013 Terrorism Deaths: African Countries with the Most Terrorist Attacks Since 2013

Twenty-three African countries have not experienced a terrorism-related death since 2013, and 17 countries have not had a terrorism attack at all. Another six countries have experienced fewer than 10 deaths each.

But even in countries without reported attacks, terrorist groups can still gain a foothold, said Hussein Solomon, a political science professor at the University of the Free State in South Africa.

“All 54 African countries [are] at risk, especially when we see linkages between groups,” he said, citing reports that Boko Haram and al-Shabab have shared terrorist tactics. “There is not a single country which is unaffected by this, including my own.”