Russia launched a massive attack on Ukraine’s energy grid, leaving many in the country in the dark over the holiday. Retired Col. Jack Jacobs shares his thoughts about recent developments in Ukraine and a potential twist in North Korea’s involvement.

Ukrainian President Volodymyr Zelensky confirmed Monday more than 3,000 troops from North Korea have been killed so far fighting next to Russian forces.

Ukrainian President Volodymyr Zelenskyy said more than 3,000 North Korean soldiers have been killed or wounded fighting for Moscow in Russia's western Kursk region.

North Korea and Russia are deepening their military cooperation, as Pyongyang ramps up the supply of arms to Moscow for its war in Ukraine and receives much needed cash and oil from the Kremlin in return.

Despite their elite status, North Korea's "Storm" troops were ill-prepared for the war, South Korea's National Intelligence Service said.

North Korean troops have now entered Russia’s war with Ukraine in a major way, and some have been killed, Western officials say.

South Korea's military has said that North Korea is preparing to continue aiding Russia in its war with Ukraine, despite casualties.

There are risks of North Korea sending additional troops and military equipment to the Russian army,” Zelensky said. “We will have tangible responses to this.”

Against the backdrop of nearly 11 years of total war in Ukraine, Russia and North Korea are increasing military cooperation into a full military defense

South Korea's military said on Monday it has detected signs of North Korea preparing to send more troops and weapons, including suicide drones, to Russia to support its war against Ukraine.

In Trump-led armistice talks, the Hermit Kingdom may want a seat at the table.

"Through various sources of information and intelligence, we assess that North Korean troops who have recently engaged in combat with Ukrainian forces have suffered around 1,100 casualties," the JCS said in a statement.