Accra - Three people have died and 14 others required medical treatment after inhaling toxic fumes at a gold mine in Ghana, the company running the operation said on Friday."We can confirm that three people have died out of the inhalation of toxic fumes from our underground operations," said a spokesperson for the Shaanxi Mining Company, Maxwell Wooma.The firm, a subsidiary of the China Gold Resources Company, said the three were among 17 people who had to be rescued and taken to hospital in Bolgatanga, in the Upper East Region."Unfortunately upon arrival [at hospital] we lost two people yesterday [Thursday] and early this morning [Friday] one passed on," Wooma added.An investigation has been launched but the company said those affected were two groups of underground "cleaners" tasked with cleaning rock particles after blasting in the mine."This is the first time we have suffered this," said Wooma."We adhere strictly to the mining regulations and safety standards for the five to six years that we have been operating and developing this mine."Ghana is Africa's second largest gold producer and exports of the yellow metal, along with other minerals and oil, helped boost the country's economic growth in recent years until a recent slide.The industry involves a number of major players in the sector but small-scale, illegal gold mining has been a persistent problem and accidents frequent. In 2010, at least 45 people were killed when an illegal gold mine collapsed after heavy rains while in November 2009, at least 18 people, including 14 women, were killed.In 2013, Ghana's government said it expelled 4 700 illegal miners, most of them Chinese, attracted to the country by prospecting.