BERLIN (Reuters) - There are credible reports of massive irregularities in the Russian Duma elections, a German government spokesman said on Monday, as the vote's results were finalised.

       Russia's ruling United Russia party, which supports President Vladimir Putin, retained its parliamentary majority after an election and a sweeping crackdown on its critics, but opponents alleged widespread fraud.

       (Reporting by Andreas Rinke; Writing by Riham Alkousaa; Editing by Thomas Escritt)