Eighteen people have appeared in court in Burundi accused of helping to organize last week's failed coup against President Pierre Nkurunziza, the BBC reported on Sunday.

It comes amid what appears to be a crackdown against those suspected of involvement in the plot.

The alleged coup ringleader, Godefroid Niyombare, is still on the run.

President Nkurunziza on Saturday thanked the army for thwarting the coup and appealed for calm, although protests have continued in the capital Bujumbura.

Those who appeared in court in Bujumbura included former defense minister General Cyrille Ndayirukiye and police commissioners Zenon Ndabaneze and Hermenegilde Nimenya, said lawyer Anatole Miburo.

Miburo said they had been accused of attempting to overthrow the state.

"They were seriously beaten, in particular General Ndayirukiye," he said.