Romania said on Friday that it has found possible drone fragments near its border with war-torn Ukraine.

Drone fragments have already been found in the NATO member since Russia's invasion of Ukraine and heavy bombardments of its Danube port infrastructure.

The latest pieces were found late Thursday on an island on the Danube river in Braila county, some 20 kilometres (12 miles) from the Ukraine border.

"Fragments that appear to have come from an aerial device (drone) were identified on a piece of agricultural land on the Big Island of Braila," the ministry said in a statement.

No casualties were reported. The incident is being investigated, it added.

Romanian authorities reported other pieces from crashed drones in 2023 after Russia intensified attacks on ports in southern Ukraine, including areas bordering Romania.

While officials stressed that they did not believe the country had been intentionally targeted, following one incident in December, Romania summoned Russia's ambassador to complaining about a "new violation" of its airspace.

A 1.5-metre (5 feet) deep crater was found in an uninhabited area in Tulcea county, which faces the Ukrainian port of Reni across the Danube.

At the time, the Romanian foreign ministry condemned Moscow's "repeated attacks".