Actually, ALL orbiting satellites are being pulled back to the earth, constantly. And the lower their distance from earth, the more they must use their boosters at times. It takes an enormous amount of speed to centrifugally remain in a stable orbit. I'm not sure of the Russians' technology, but as an electrical engineer, I doubt they used lasers. I would place my bets on data manipulation/programming.  One example - Trick the satellite into thinking it's orbiting too fast, and it will slow down...and the slower it gets, the faster it draws back to earth.  Do that, and put the code in emergency security mode, which would force a timed wait to make a change (I often have to implement this in my programs for Chemical plants), and boom.