African Barrick Gold PLC says seven intruders were killed and a dozen more were injured at its North Mara mine in Tanzania.
The company controlled by Barrick Gold Corp. of Toronto says 800 "criminal intruders" were trying to steal ore from the mine when police were called.
It says the thieves attacked the police with machetes, rocks and hammers.
African Barrick says the police have increased their presence in the area and launched an investigation.
The company has also started its own internal review.
Barrick Gold Corp. , the world's largest gold miner, holds a roughly 74 per cent stake in African Barrick, which owns the company's former mines in Tanzania.