Updated

Ugandan police say a child has been killed and eight others seriously injured in an explosion in a suburb of the capital, Kampala.

Police spokesman Fred Enanga told The Associated Press the explosion late Wednesday happened at a school playground where children were playing with an explosive device that they did not recognize. He said the device was a suspected hand grenade and that security officials have been sent to investigate.

He said he believed the incident had nothing to do with the general election scheduled for Thursday. Tensions have been rising ahead of the vote that pits long-time President Yoweri Museveni against seven challengers.

Museveni's main rival, Kizza Besigye, has said he doesn't believe the election will be free or fair.