CAIRO (Reuters) - Egypt's military has arrested and tried more civilians before military tribunals than those brought before them during the 30-year rule of former president Hosni Mubarak, Human Rights Watch said on Saturday.

"Nearly 12,000 prosecutions since February is astounding and shows how Egypt's military rulers are undermining the transition to democracy," Joe Stork, deputy Middle East and North Africa director at Human Rights Watch, said in a statement.

Egyptian activists returned to Cairo's Tahrir square on Friday to demand a clear road map to democracy and an end to military trials for civilians.

Rights groups say the trials, held behind closed doors, were a common practice under Mubarak and their continued use shows how far Egypt has to go to guarantee the rule of law.

The army had said on Sep. 5 it would stop trying civilians in military courts when it scraps the country's decades-old emergency law.

The ruling generals say the military trials are a temporary but necessary measure to deal with a wave of disorder and an increase in criminality following Mubarak's ouster.

But an end to emergency law alone would not guarantee an end to the practice, Human Rights Watch said.

Under the Code of Military Justice, the army can bring civilians before military tribunals for crimes committed in an area controlled by the military, the rights group said.

"The Egyptian authorities should amend the Code of Military Justice in line with its obligations under international law to limit military jurisdiction to military offences," Stork said.

(Reporting By Maha Dahan; Editing by Ruth Pitchford)

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