On Monday, the Islamic State claimed it had killed scores of Iraqi troops and captured one soldier in an ambush near the al-Tanf border-crossing along the Iraqi-Syrian border.  Kata'ib Sayyid al-Shuhada (K.S.S.), an Iranian-backed unit of the Iraqi Popular Mobilization Forces (P.M.F.), however, blamed U.S. air strikes for its losses and vowed revenge. The U.S.-led coalition the allegation.

While conflicting accounts of the incident continue to surface, a survey of reports prior to and in the wake of the attack helps us get a clearer image of the event.

On August 2, Iran’s Fars News Agency : “The ISIL terrorist group has prepared a large number of fighters and a large volume of military hardware in two desert regions in Anbar province in Western Iraq to storm border crossings with Syria and Jordan to slow down Iraqi forces’ rapid advances there.”

A day after the attack, however, Karim al-Nouri, a P.M.F. spokesman, told Lebanon’s al-Mayadeen TV that “the U.S. threatened Hashd al-Shaabi [P.M.F.] and then acted against them.” He claimed that the U.S. military now blamed it on the Islamic State to sway public opinion in Iraq and around the world.

Interestingly, Iranian state-run outlets backed Washington’s account that the Islamic State was behind the attack. Defa Press identified that one I.R.G.C. soldier captured and then killed by the Islamic State was , a native of Iran’s Isfahan Province serving in the I.R.G.C.’s 8th Najaf-e Ashraf Armored Division.

The Iraqi [Fatwa of the Sacred Defense] website, which regularly releases information about P.M.F. combat fatalities, also refuted K.S.S. account.  On Wednesday, the website released the names of four P.M.F. fighters killed “in the frontiers of Iraq” on August 7: , , , and . The site described the four individuals killed as “martyrs of the fatwa of the sacred defense,” referring to Iraq’s Grand Ayatollah Ali Sistani’s June 13, 2014 call to arms against the Islamic State. This indicates the P.M.F. fighters were killed in an Islamic State ambush rather than in US air strikes.

The motives behind K.S.S. commander’s accusations against the United States are unclear. K.S.S. may have found it embarrassing to admit his forces were killed by the Islamic State although the terrorist group had announced its plan for the attack.

Nouri may also have found it more honorable to claim his men were “martyred” by the superior U.S. Air Force rather than a terrorist group on the verge of collapse.

Regardless of Nouri’s motives, this incident raises the bigger question of the fog of war or disinformation.

The United States has attacked Tehran’s proxies in Syria in the past, and Tehran at some point may believe accusations such as Nouri’s. To what length are Tehran’s proxies likely to go in advancing their own interests regardless of the strain it may put on relations between Tehran and Washington? How would Tehran react to such attacks in the future if it thinks are carried out by the U.S. military against its proxies? What mechanisms are in place in Tehran and Washington to avoid further escalation of such conflicts?

It appears that the August 7 incident will not trigger a confrontation between Tehran and Washington as K.S.S. account is inaccurate. However, with relations between Tehran and Washington deteriorating fast, the potential for conflict between the countries is very real. Next time an Iranian proxy engages in disinformation campaigns for any reasons, the consequences may be grave.