Nobody has ever revealed why American and Soviet forces attacked each other during the Niš Incident

During the Second World War , the United States and the Soviet Union joined forces to fight against Germany. That's why it was so unexpected when, in late 1944, American pilots started attacking Red Army ground troops stationed close to the Serbian city of Niš.

The reasons for this attack remain uncertain, as neither side has ever provided an explanation. Nonetheless, the Niš Incident is remembered as an important instance of tragic friendly fire.

A big mistake by the American forces

On November 7, 1944, the Soviet 6th Guards Rifle Corps pushed towards Belgrade, Serbia, aiming to bolster the Hungarian front in the south against possible enemy assaults.

At the same time, the US 82nd Operations Group (82 OG) was delivering air support to the Red Army. However, a huge mistake occurred that day. The Americans were evidently unaware that the Soviets had advanced 100 km beyond their anticipated position. Despite assurances from the US Mediterranean Air Force command that no German forces were near Niš, the 82nd proceeded with an attack.

It appears they mistakenly mistook the advancing Soviet troops for German forces.

Friendly fire dogfight

A group of Lockheed P-38 Lightnings open-fired on the Soviet convoy. It's unclear how many American aircraft were involved in the attack, but the Red Army quickly retaliated, believing them to be Luftwaffe -flown Focke-Wulf Fw-189 Uhus .

Orders were given to Soviet pilots, based out of the nearby Niš Constantine the Great Airport, to aid in the engagement. Multiple Yakovlev Yak-9 and Yak-3s flew to the area, immediately engaging with the P-38s in an action-filled dogfight. It took some time, but the Red Army aviators eventually identified the white stars on the American fighters and laid off their weapons.

Lasted just 15 minutes

From the ground, the Soviets tried to signal the Americans, indicating that they were targeting their own allies. However, for some reason, the Americans failed to notice. It wasn't until the Soviets displayed the large Red Star on their fighters that the American pilots realized they were attacking an ally and promptly withdrew.

What came to be known as the Niš Incident lasted only about 15 minutes. Though brief, it was long enough for both sides to lose aircraft.

Reason is still unclear

The exact cause of the Niš Incident is still unclear. The official account claims that American forces mistook Red Army troops for Germans, but the full details remain classified. Many suggest there could have been another motive behind the attack. With tensions between the United States and the Soviet Union running high at the time, some believe the incident reflected the strained relations between the two nations.

Whether this theory is accurate or not will remain unknown until the information is declassified.

Each side has a different account of the event

Each side maintains their own account of what happened. The number of casualties for each varies, with the Soviets suffering between 31-34 casualties, around 37-39 wounded and 20 cargo trucks burned. The US contends that four Soviet aircraft and two P-38 Lightnings were lost that day, while the USSR claimed the total was actually two Yaks and five P-38s.

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Ultimately, the US military apologized for the mistake.