President Robert Mugabe's Zanu-PF party is criticised
The reports, one by a coalition of non-governmental organisations called the Zimbabwe Human Rights Forum and the other by a group of Danish doctors, say the government is overwhelmingly responsible.
It comes as the government again fails to push through a controversial media bill, after ruling party MPs in parliament were critical of the bill's shortcomings.
The bill, which critics say is part of President Mugabe's drive to silence opposition to his bid for re-election in March, is now tabled to be discussed in parliament next Tuesday.
Under the controversial proposals, foreign journalists would not be allowed to be based in Zimbabwe.
All local media organisations would have to apply for annual government licences or face two years in prison.
And reports deemed to cause alarm and despondency would be forbidden.
The bill is one of several pieces of legislation which analysts say are key to Mr Mugabe's campaign to win the 9-10 March presidential elections, when he is likely to face a strong challenge from the opposition leader Morgan Tsvangirai of the Movement for Democratic Change.
Violence
The forum says there was a sharp rise in violence in the first half of January.
It reports four deaths, 68 cases of torture and 22 kidnappings during that period.
It says much of the violence was carried out by youths from the ruling Zanu-PF party, who have put up roadblocks across the country, demanding that people buy party memberships cards.
The Danish Physicians for Human Rights says politically motivated violence in Zimbabwe is widespread and increasing on a daily basis.
It says the government was responsible for all the cases it studied and the violence was carried out in a way that clearly indicated planning and strategy.
Supporter murdered
Both reports link the violence to the March presidential elections.
Zimbabwe's state-controlled media acknowledges the increase in violence, but says the opposition MDC is also responsible.
It says a Zanu-PF supporter was murdered on Sunday in Masvingo province, south of Harare.
And it accuses the opposition of setting up a number of safe-houses in the capital, from which it conducts raids on Zanu supporters.