Witnesses say police in Congo's capital have used tear gas to disperse crowds gathered outside the home of longtime opposition leader Etienne Tshisekedi.

The 84-year-old Tshisekedi died Wednesday evening in Brussels, where he had been undergoing medical treatment.

On Thursday, his supporters gathered outside his Kinshasa home to show their support and renew calls for President Joseph Kabila to step down.

Tshisekedi's death comes a few weeks after Kabila's party and the opposition signed an agreement that calls for new elections later this year in which Kabila will not run.

But there are already concerns about how his death will affect the implementation of the deal.

Tshisekedi founded his opposition party in 1982 and was heavily involved in the deal's negotiations.