STORY: The officers photographed the woman, who was holding up a sign, before taking her away.
Reuters could not immediately verify what was written on the piece of paper.
Gorbachev, who died on Tuesday (August 30) aged 91, was set to be buried without state honours or President Vladimir Putin in attendance.
He was however granted a public send-off, with authorities allowing Russians to view his coffin in the imposing Hall of Columns, within sight of the Kremlin, where previous Soviet leaders have been mourned.
After the ceremony Gorbachev will, be buried in Moscow's Novodevichy cemetery alongside his wife Raisa, who died 23 years ago.