Authorities have arrested more than 11,000 people since Ethiopia declared a state of emergency in early October amid violent protests, state TV said on Saturday.
Ethiopia has been in political crisis for around a year with frequent outbreaks of violence as authorities have brutally cracked down on anti-government demonstrators.
"Some 11,607 individuals have so far been detained in six prisons, of which 347 are female, in connection with the state of emergency declared in the country," State of Emergency Inquiry Board chairperson Taddesse Hordofa said in a statement broadcast by EBC.
Hordofa reeled off a long list of offences ranging from serious crimes such as "attacking security forces using firearms" or "killing civilians and members of security forces" to the much more mundane "denying provision of public services" and "disrupting movement of vehicles".
This figure is a huge increase on the 2,500 arrests that Ethiopian Prime Minister Hailemariam Desalegn's government had announced at the end of October.
The six-month state of emergency was declared on October 9, an unprecedented move by the current government, which has been in power for 25 years.
Unrest in the country had begun in the central Oromo region and then spread to Amhara in the north, causing hundreds of deaths, according to human rights organisations.
Those regions are where the majority of arrests have been made and make up 60 percent of the country's population.
On October 31, Ethiopian defence minister Siraj Fegessa announced that 2,000 people who had participated in protests had been released, although Saturday's announcement included no details on how many of the 11,000 remain in prison.