Ukraine has reported an air-drop by Russian forces of explosive devices into the grain corridor for ships transporting exports.

The incidents occurred in the early hours of Wednesday.

A statement posted on the Operational Command South’s Facebook page said they involved “four unidentified weapons (probably bottom mines) in the Black Sea in the direction of the navigation corridors of civil shipping”.

“The operational situation in the area of responsibility of the Defense Forces of Southern Ukraine remains steadily tense,” the statement added.

A spokesperson for the Command said: “For several days, there were no flights of Russian aircraft in the area of sea transport routes.”

“However, on the 25th of October, they intensified their activity and dropped four explosive devices. Presumably, this is done to disrupt the movement of civilian vessels and discredit the defence forces of Ukraine, as we continue to ensure the security of the humanitarian corridor used by ships from around the world,” the spokesperson added.

There have been three reports in recent weeks of mines hitting or exploding near cargo ships.

Security company Ambrey has previously reported that Russian forces have been targeting the transit routes to Ukraine’s ports by deploying sea mines.

It believes Russia will continue to use tactics that offer a level of plausible deniability.

A direct attack on a merchant vessel would result in increased freight rates and insurance coverage in the region, which would harm Russian interests and likely decrease export volumes from Russian Black Sea ports, Ambrey said.

The company argues Ukraine has “no vested interest in falsely claiming that Russia is targeting the grain corridor because this could discourage vessels from calling [at] Ukraine’s sea ports”.

Devices unlocated?

Ukraine has not said its forces have managed to locate and destroy the devices.

Six vessels were waiting east of Sulina anchorage in Romania to head to Ukraine’s seaports on Wednesday morning.

At the start of October, the UK government warned Russia could resort to using mines to target civilian shipping in the Black Sea, citing newly declassified information.

The UK’s Foreign, Commonwealth and Development Office said Moscow’s tactics would include laying mines in the approach to Ukrainian ports and laying the blame on Ukraine for any attacks.