Russia's dollar-denominated RTS stock exchange index dropped 4.79 percent compared to the previous close, while the country's ruble-denominated MICEX index fell 3.73 percent at closing on Thursday amid gloom on international trading floors.
As of 18:45 Moscow time, the RTS index amounted to 1,584.20, the MICEX index to 1,452.83. The both indices broke their week lows.
Leading European stock indices also plunged on Thursday due to spreading fear of slowing world economic growth and poor bank results.
By 15.14 GMT, London's FTSE 100 dropped 4.26 percent to 5,104.64, Frankfurt's Dax lost 5.06 percent to 5,648.15, while France's Cac 40 went down 5.01 percent to 3,091.42.