An opposition supporter was shot on Monday during clashes with police at a campaign event in Uganda’s capital.
Police spokesman, Fred Enanga, confirmed on Tuesday that one civilian was killed in scuffles and that police had fired rubber bullets to disperse presidential candidate Kizza Besigye’s supporters.
Presidential elections in Uganda will take place on Thursday and precaution has already started to take place by security forces.
Kizza Besigye believes that the elections will not be free and fair.
"Our people spoke with one voice and gave a simple message that they want change," Besigye told reporters on Tuesday.
"That was a very strong and direct message everywhere we went."
Museveni, who is campaigning for re-election, has ruled Uganda since 1986, when he led a group of rebels who had waged a bush war against a government they accused of rigging elections.
Leading election monitors from the European Union, Eduard Kukan told reporters he would raise concerns with the election commission over the voters' registry.
Gen. David Sejusa, who has called President Yoweri Museveni a dictator, is being detained at a military barrack in the Ugandan capital Kampala since last month.