Congolese Opposition leader Etienne Tshisekedi arrived in Kinshasa on Wednesday from a two year stay overseas for medical treatment.
Hundreds of thousands lined the streets to welcome him home. Tshisekedi formed Congo's first organised opposition platform in 1982.
He came in second in the 2011 polls that saw President Joseph Kabila re-elected. His arrival comes at a crucial moment in the country's political landscape.
The November presidential elections are in doubt. It's feared President Kabila will seek to extend his term beyond the constitutional mandate.
Tshisekedi's supporters hope his return will rally people to push for elections to take place as scheduled.