The Rwandan government says “defensive measures were taken” on a Democratic Republic of Congo fighter jet that “violated" its airspace on Tuesday evening.
Images shared on social media show a military plane being shot at while flying at a low altitude between the towns of Goma in DR Congo and Gisenyi in Rwanda.
Other images show the damaged plane – a Soviet Union-made Sukhoi-25 – being cooled down with water at Goma airport.
In a statement, DR Congo's information ministry condemned the incident and denied that its jet had flown over Rwandan airspace.
It said the government "does not intend to let this [incident] go" and had the "legitimate right" to defend itself.
"The government considers this umpteenth attack by Rwanda as a deliberate action of aggression that is equivalent to an act of war," the ministry noted.
Rwanda said this was the third incident involving a Congolese fighter jet on its airspace and asked its neighbour "to stop this aggression”.
Last November, a Congolese Sukhoi-25 jet briefly landed at Gisenyi airport in Rwanda. Kinshasa said the fighter jet had “mistakenly landed” there.
DR Congo accuses Rwanda of supporting M23 rebels, which Kigali authorities have consistently denied.
The latest incident adds to the tensions between the two neighbours.