The Military Times published on 29 September 2016 an article titled "Attacks on U.S. Troops in Somalia Leads to Airstrikes on al-Shabaab" by Andrew Tilghman.
The account reports two recent occasions when small numbers of US troops (presumably Special Forces) came under attack in Somalia from al-Shabaab and the US launched "self-defense" airstrikes in response. The first attack occurred on 26 September outside Kismayu in southern Somalia where the Pentagon said the strike killed 9 enemy fighters. The second attack occurred on 28 September in central Somalia near Galkayo where the Pentagon said the strike killed 4 al-Shabaab fighters.
The government of "semi-autonomous" Galmudug State issued a press release stating that the second attack mistakenly killed 13 Galmudug forces and injured another 7. The government of Galmudug State called for an apology and compensation from the United States.
Following a Pentagon investigation, it was confirmed that the American drone strike killed 10 members of a regional force allied with the United States. The Washington Post published on 10 November 2016 an article titled "After Initial Denial, Pentagon, Discovers It Killed 10 Allies in Drone Strike in Somalia" by Kevin Sieff.