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Ukrainian forces have taken prisoner a Russian lieutenant colonel specialised in electronic warfare, western officials have said.
The captured officer is possibly the most senior Russian figure to be held as a prisoner of war, and is likely to yield vital intelligence on the military's electronic jamming and signals interception capabilities.
“We are looking more into this, but in the area in which he was captured there was a significant amount of electronic warfare equipment,” the official said.
Electronic warfare was meant to be an important asset in Russia’s initial offensive, allowing it to track Ukrainian unit movements, locate and jam drones, and eavesdrop on top-level conversations.
However, it has so far proved to be less than effective and its abilities will decline with the high-profile capture.
Meanwhile, the six Russian generals who have been killed during the campaign, including an army chief, have all now been replaced, a security source confirmed.
Reinforcements coming in to replace the estimated 10,000 Russian dead and 20,000 wounded are reportedly experiencing low morale after hearing accounts from those fighting in the first wave, it has been disclosed.
Suffering very high casualties, the Russians have been mobilising troops from across the country to reconstitute its forces “because they've had such significant losses so far,” the official said.
“Those units that come forward are likely to be more poorly equipped than the professional units that came in the first instance," the official said. "Their morale is likely to be more fragile when they come forward, having heard about what's happened to the first-line forces and that have come through."
It appears that there is less optimism on how long the Ukrainian defenders of the strategic southern city of Mariupol can hold out. The Russians have been using “dumb munitions” — heavy bombs that are causing heavy civilian casualties.
But Ukrainian forces were getting much-needed weapons and supplies of ammunition, taking them from dead or captured Russian troops, the official said.
The official was asked if the very high casualty figure — almost equal to that suffered by Soviet troops in Afghanistan during more than a decade of fighting — was having an impact on Russia's leadership.
“Putin himself probably has a pretty high tolerance for casualty rates and therefore the willingness at the most senior political level to pour more resources in is really significant,” he said.