JOHANNESBURG (Reuters) - Harmony Gold said violent clashes erupted between rival unions at its Kusasalethu mine in South Africa on Thursday, raising concerns labor unrest was flaring again in Africa's largest economy days after a wave of wildcat strikes ended.

Spokesperson Marian van der Walt said the conflict was between the National Union of Mineworkers and the Association of Mineworkers and Construction Union. The turf war between the two has been at the root of much of the violence rocking the sector.

(Reporting by Sherilee Lakmidas; Editing by Ed Stoddard)