JOHANNESBURG (AP) ― Repression by Congo’s government ahead of this month’s critical presidential election could lead to even more violence in the Central African nation struggling after decades of dictatorship and civil war, the United Nations warned Wednesday.

The report from the U.N. Joint Human Rights Office in Geneva said people have been beaten and arrested just for wearing opposition party T-shirts. One man has been jailed since March for selling a newspaper that questioned President Joseph Kabila’s nationality.

The U.N. said security is in the hands of “heavily underpaid, and poorly trained and equipped” security forces and police.

“The continued repression of human rights and fundamental freedoms in the pre-electoral period may increase the likelihood of individuals and political parties resorting to violent means, endanger the democratic process and lead to post-electoral violence,” the report says.

The Nov. 28 presidential vote will be only the country’s second democratic election in a half century. The first one in 2006 was largely organized and secured by the massive U.N. peacekeeping mission in Congo. Even so, it was marred by deadly clashes between soldiers supporting Kabila and those backing his most powerful rival, Jean-Pierre Bemba.

Kabila has vowed that he is committed to holding a credible and democratic vote. He is widely expected to win after he changed the electoral system from two rounds of voting to a first-past-the-post single round.

The plethora of opposition candidates note this assures Kabila of victory unless they unite behind a single a candidate, but they have been unable to overcome their egos and political ambitions to agree on one candidate.

Already there are signs of growing tensions with the vote still weeks away. Several people already have been killed and injured. Over the weekend, 16 were wounded in the southeast mining center of Lubumbashi during fighting between supporters of two rival opposition candidates.

A U.N. Security Council resolution back in June urged the Congolese government and all relevant parties to “ensure an environment conducive to a free, fair, credible, inclusive, transparent, peaceful, and timely electoral process.”

Radio and TV stations supporting the opposition have been suspended, and opposition parties are not given equal access to state-controlled media.

Some political rallies have been banned, others forcefully dispersed by police. The report says there has been some improvement in the behavior of police, who earlier this year attacked unarmed and peaceful opposition protesters with batons, tear gas and firing live rounds into the air.

Opposition party members discussing the political situation in a barber shop were detained by the owner, who happened to be a soldier. They were illegally held at a military camp where they were beaten and ill-treated, the report said.

The report says there is particular concern for eastern Congo, where numerous militias and foreign rebels continue to terrorize the population. It said Rwandan-led rebels have threatened to destabilize the elections and in September started destroying voters’ cards in two villages of North Kivu province to prevent people from taking part in the elections.

The report said the 188 violations it has documented in the year leading up to elections form “only a portion” of all the human rights violations committed against political opponents, human rights activists and journalists. Most are blamed on the government.