Russia likely deploying 'unreliable and unpredictable' butterfly mines in Ukraine, UK intel says. The munitions reportedly maimed children in past wars.

• Russia is likely using "unreliable and unpredictable" butterfly mines in Ukraine, UK intelligence said.
• Children mistook the mines for toys when they were used in the Soviet-Afghan War.

Russia is likely using "unreliable and unpredictable" butterfly mines in Ukraine that children could mistake for toys, the UK Defense Ministry said Monday in an intelligence update.

British intelligence said Russia is "likely deploying anti-personnel mines to protect and deter freedom of movement along its defensive lines in the Donbas."

Usage of these PFM-1 and PFM-1S mines — also known as butterfly mines — has been decried by international watchdogs. They are banned as part of the 1997 Mine Ban Treaty; neither Russia nor the US have signed the treaty, though Ukraine has.

The mines — which has two plastic wings to help it drift to the ground — contain about 40 grams of explosives, according to the Imperial War Museum. Just 11 pounds of pressure is enough to set off the mine, the War Museum states.

Russian forces have used at least seven types of antipersonnel mines since it invaded Ukraine earlier this year, Human Rights Watch said in a report in June. There is no credible evidence that Ukraine has deployed anti-personnel mines, the nonprofit group found.

These types of mines were used in the Soviet-Afghan War where they "allegedly maimed high numbers of children who mistook them for toys," UK intelligence said.

Since these mines have not been used since the Soviet era, the UK Defense Ministry predicts that their usage is now "highly unreliable and unpredictable."

"This poses a threat to both the local population and humanitarian mine clearance operations," the update from the UK Defense Ministry said.

The Ukrainian Military said Sunday that Russia attacked Donetsk, but the Ukrainian army was able to push back enough to prevent attacks in other places.

"With offensive actions, the enemy tried to improve its tactical position near Verkhnokamianske but was unsuccessful and retreated," the General Staff of the Ukrainian armed forces said.

The General Staff added that Russia is "concentrating its main efforts on preventing the advance of our troops."