WASHINGTON — The roadside bomb that disabled an American vehicle in Niger last week was rudimentary and harmed no one, but its location — roughly 70 miles into the country’s interior and minutes from an American Army outpost — was unusual and alarming, military officials said.
The strike was the latest in a string of attacks carried out by Islamic State affiliates using roadside bombs in Niger that have, until now, mostly targeted Nigerien forces.
No extremist group claimed responsibility for the blast, which occurred on the outskirts of the small town of Oullam. The blast’s proximity to American troops has increased concerns about the growing threat of improvised explosive devices, or I.E.D.s, that have long defined American conflicts in Iraq and Afghanistan.
The bomb used on June 8, according to a military official, was activated by a weatherproofed pressure plate and wired to an 81 millimeter mortar projectile, which exploded, causing a main charge of nearly a dozen 60 millimeter mortar rounds to detonate. The explosives were buried roughly three feet underground and positioned at a key choke point on a road that led to a shooting range frequented by American, Canadian and Nigerien troops.
A roughly 12-ton American all-terrain vehicle, known as a M-ATV, with soldiers from the 19th Special Forces Group inside, triggered the device. According to a military official familiar with the blast, the bomb was packed similarly to one used in northern Niger this year. If a lesser-armored vehicle had detonated the explosives, there would have been significant casualties, the official said. Little else is known about the bomb.
Despite military efforts in the region, including a concerted and continuing counterterrorism mission led by France throughout the Sahel since 2014, extremist groups there are expanding their efforts to strike further afield than they have in the past.
Andrew Lebovich, a visiting fellow at the European Council on Foreign Relations who focuses on North Africa and the Sahel, said that the spate of roadside bomb attacks highlights the growing threat that American and French forces are facing in Niger despite their efforts.
“It’s an evolving threat and it’s spreading,” Mr. Lebovich said. He added that militants in Niger are varying their assaults with improvised explosive devices in addition to their often-used tactic of staging ambushes primarily from motorcycles.
On Oct. 4, 2017, Islamic State militants attacked an American Special Forces team of 11 soldiers alongside roughly 30 Nigerien troops in much the same way, leaving four Americans and five Nigeriens dead. A recently released redacted report detailing the ambush pointed to an intelligence failure as one of the reasons that the small American force was caught off guard by a large Islamic State force on the Niger-Mali border.
Last month, at least 25 Nigerien soldiers were killed in an ambush near Tongo Tongo, the site of the October 2017 gunbattle. The attack was carried out by Islamic State militants who used a combination of small arms and at least one roadside bomb.
Roadside bombs have been nearly nonexistent in this part of the country until recently. According to a United Nations report published last month, the first roadside bomb to target Nigerien forces in northwest Niger was during a Jan. 31 attack, which left four soldiers wounded.
Since then, there have been at least six more episodes involving improvised explosive devices in western Niger, according to data compiled by Heni Nsaibia, a researcher with the Armed Conflict Location & Event Data Project. But in southeastern Niger, the weapon has been used against government forces fighting Boko Haram around Diffa, Niger, since 2015.
The growing presence of roadside bombs is not just a problem in Niger. In central Mali, according to the United Nations secretary general, roadside bomb attacks have more than tripled to nearly 100 in 2018 from 29 in 2017.
Col. Christopher Karns, a spokesman for Africa Command, said that American forces provide counterroadside bomb training to local forces, but he would not comment on the growing threat from the hidden explosives, nor on the details of the June 8 blast.
“Doing so, presents potential information to adversaries and we’re not in the business of doing that,” Colonel Karns said in an email.
There are roughly 800 American forces in Niger consisting of Special Operations forces and support troops who are now finishing a large drone base outside the city of Agadez. In 2018, the Pentagon said it would start withdrawing some forces from Africa, including from Niger, to better prepare for possible conflicts with Russia and China.