Maya Abromchyk claims she was severely beaten by OMON troops who on December 19 forcibly dispersed supporters of opposition presidential candidates gathered on Minsk's Independence Square.
Abromchyk sustained a broken leg and underwent two operations. She still needs further surgery. Doctors say her leg was broken by a hard object, such as a police truncheon.
Despite that testimony, the Minsk prosecutor's office ruled it will not investigate the possible involvement of OMON troops or other security forces in the case.
Abromchyk was able to walk without crutches for the first time last week. Doctors say it is unclear if she will fully recover from her injuries.
An estimated 15,000 people rallied in Minsk on December 19 to protest the official results of the presidential election that gave incumbent President Alyaksandr Lukashenka an overwhelming victory.
Opposition activists say the vote -- which international election monitors said was flawed -- was fraudulent.
Police and security forces violently dispersed the demonstration, beating activists and taking scores of them to detention centers, including most of the opposition presidential candidates.
Dozens of activists have since been tried and found guilty of beating police or "taking part in mass unrest" and sentenced to various prison terms.
-- RFE/RL's Belarus Service