Prosecutors said Friday they summoned the former ambassador to Cameroon for questioning on whether he tried to cover up his name when sending an overblown report on the size of diamond reserves in a mine in the African country.

Lee Ho-sung is one of the key figures involved in allegations that senior government officials and CNK International, a resources mining company, engaged in insider trading to boost the stock price of the company, which won diamond-mining rights in Cameroon.

Earlier, independent lawmaker Jeong Tae-keun raised suspicions that Lee used his subordinate diplomat’s name in a diplomatic cable sent to the Foreign Ministry in 2010 that positively evaluated the reserves.

The cable was sent under the name of the first secretary of the embassy, who reportedly hesitated to write the wire because he believed the size of the diamond reserves lacked evidence.

Kim Eun-seok, then energy and resources envoy, led the Foreign Ministry to release a press release on CNK’s winning of the mining rights, based on the wire sent by Lee.

On Dec. 16, 2010, CNK’s joint venture C&K Mining won the bid to develop the diamond mine in Yokadouma in the southeast of the country. Because of the potential economic benefits to Korea, Seoul government officials, including former Vice Minister of Knowledge Economy Park Young-june, had helped the firm win the deal.

On Dec. 17, Seoul’s Foreign Ministry issued the press release, in which it said the mine held an estimated 420 million carats in diamonds. After the announcement, CNK’s stock price jumped fivefold in less than a month.

By Kim Yoon-mi (yoonmi@heraldcorp.com)