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- A Ukrainian military official said Russia's defensive lines have weak points.
- Russia constructed defensive lines known as "dragon's teeth" to protect its positions.
- In recent days, Ukraine has made some progress in its bid to breach them.
Russia's infamous "dragon's teeth" defenses were mocked by a Ukrainian former commander, who claimed they were easily breached by Ukraine's tanks.
The concrete pyramids, which stand about four feet tall, are meant to block and damage Ukrainian tanks and other armored vehicles.