Police in Congo’s capital Kinshasa fired tear gas on Friday to disperse around 100 protesters calling for the expulsion of the Rwandan ambassador they accuse of denying a massacre during the 1998-2003 Congo war.

Two people were seriously injured, one of whom was in critical condition, after inhaling tear gas and being beaten by police, said Carbone Beni from the campaign group Filimbi, which organised the protest.

Kinshasa’s police chief Sylvano Kasongo confirmed some protesters were hurt, but said injuries were not serious. The city’s governor had not authorised the demonstration, he said.

The protest was broken up before the group reached the Rwandan embassy.

In August, Ambassador Vincent Karega responded to a Twitter post that accused Rwandan troops of killing more than a thousand people in the east of the Democratic Republic of Congo in August 1998.

“Blatant incoherence between image and history... accusation without evidence is called slander,” Karega tweeted and later deleted.

Karega told Reuters on Friday his comments had been misinterpreted and he did not deny that a massacre had taken place. He said he was thankful for the level of organisation shown during Friday’s protest.

Millions died of conflict, hunger and disease during the war in eastern Congo. Rwanda was one of several neighbours that intervened, and many Congolese blame their smaller neighbour for provoking the conflict.

Relations between Rwanda and Congo have been turbulent for decades, although ties have improved in recent years.