* Two defeated presidential election candidates arrested
* Pair wanted to march over high food, fuel costs
(Adds details, colour, detention of second leader)
By Elias Biryabarema and Justin Dralaze
KAMPALA, April 11 (Reuters) - Ugandan police detained two opposition leaders on Monday as they prepared to march in protest over rising food and fuel prices in the east African country, Reuters witnesses said.
Police detained Kizza Besigye, President Yoweri Museveni's closest rival in February elections, at his home in the capital Kampala. A Reuters witness said Besigye was bundled into a police vehicle.
"We condemn this blatant abuse of human rights and use of violence on innocent people," he told KFM radio as he was taken away.