Defying a ban on demonstrations, hundreds of supporters of Marc Ravalomanana took to the streets of the capital Antananarivo to rally on the square outside City Hall, with police firing tear gas to disperse them.
Several demonstrators hurled Molotov cocktails at officers, who arrested four people, the correspondents said.
After a brief game of cat-and-mouse with police chasing demonstrators, the heavens opened and a torrential downpour quickly clearing the area.
Police had also used tear gas at a similar demonstration on Wednesday.
Angry protests erupted on December 29, just two days after former president Andry Rajoelina was declared the winner of a runoff vote which took place 10 days earlier.
Defeated, Ravalomanana — also a former president — cried foul, claiming fraud and demanding a recount of votes in the Indian Ocean island state, which has a long and bitter history of instability.
He has lodged an appeal to the Constitutional Court, which is due to hand down its ruling on January 8, and his supporters have vowed to keep up their protests until then.
“It’s not fair that they have dispersed us with tear gas, we are just ordinary citizens who want to know the truth about what happened at the ballot box,” said 53-year-old protester Jean-Paul Rasolon.
“After January 8, if they don’t establish the truth, and it doesn’t matter who wins, we will be in a crisis,” he warned.
In the December 19 runoff, Rajoelina, who was previously in office from 2009-2014, won nearly 56 percent of the votes while Ravalomanana, who served as president between 2002-2009, took just over 44 percent.
Both men were banned from running in the election of 2013 as part of an agreement to end the recurring crises that have rocked Madagascar since independence from France in 1960.
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