Cape Town, Jan 10 (IANS): The South African government Thursday directed its officials to expedite the investigation into Rwandan former intelligence chief Patrick Karegyeya's death.

The government will ensure that no stone is left unturned in tracking and bringing to justice those involved in this criminal act, Xinhua quoted the Government Communication and Information System (GCIS)in a statement.

Patrick Karegyeya, the former director of the Rwandan External Intelligence Service, was found dead Jan 1 in his hotel room in Johannesburg's Sandton city.

The initial investigations indicated that there were signs of a scuffle and a bloody curtain cord and towel which were in a safe in his room.

The Justice, Crime Prevention and Security Cluster of the Government "is saddened by the untimely death of Colonel Patrick Karegyeya and passes condolences to his wife and children," the GCIS said.

Karegeya, an important opposition figure, went into exile in South Africa seven years ago after being sacked as head of President Paul Kagame's external intelligence.

The opposition Rwanda National Congress (RNC) alleged in a statement that Karegeya was assassinated by the Rwandan authorities, but the Rwandan government vehemently denied the allegation.

In 2011, a Rwandan military court sentenced Karegeya and others to 20 years in prison for threatening state security after they were tried in absentia.

Former Rwandan army Chief Faustin Kayumba Nyamwasa, who fled to South Africa with Karegeya, had survived an assassination attempt in 2010 which took place outside his Johannesburg home.