LUSAKA (Reuters) – Zambia police said on Tuesday four suspects have been arrested in connection with a string of grisly ritual murders in the southern African nation’s capital that triggered anti-foreign riots targeting mostly Rwandan migrants in April.

The arrested suspects are two army soldiers, a civilian employee of the Zambian Air Force and a traditional doctor, police said. They were to appear in court Tuesday afternoon charged with seven counts of murder.

“All the murders which the accused have been charged with were committed in a similar manner by crushing the left side of the head, removing body parts and later dumping the deceased near their homes,” police said in a statement.

Police said in April that the victims had ears, hearts and genitals removed, raising suspicion of ritual killings.

Human body parts are sometimes used in traditional remedies and concoctions in southern Africa. The practice is linked to witchcraft beliefs.

Zambia hosts thousands of refugees from neighboring countries, especially Rwanda and Burundi, but relations between the communities are usually peaceful.

(Reporting by Chris Mfula; Writing by Ed Stoddard; Editing by James Macharia)