Bodies of James Bethel and Gerrit Strydom, who had both worked for the former FTSE 100 group, discovered in separate rooms in Missouri

Two men who had been colleagues at the former FTSE 100 mining group Eurasian Natural Resources Corporation have been found dead at a hotel in the US.

The bodies of James Bethel, 44, the former head of the group’s copper and cobalt division in the Democratic Republic of the Congo, and Gerrit Strydom, 45, who was the general manager of ENRC subsidiary Congo Cobalt Corporation, were discovered last weekend in separate rooms at the hotel in Springfield, Missouri.

The men, understood to be from South Africa, were on holiday riding motorcycles on Route 66. Preliminary results of autopsies completed by the Greene County medical examiner showed no signs of foul play, according to the local television station KY3. The causes of the deaths continue to be investigated and toxicology reports have been requested.

A spokesman for ENRC Africa said: “It is with great sorrow that we were informed about the passing away of James Bethel and Gerrit Strydom. We can confirm that Gerrit Strydom was the general manager of the group’s CCC [Congo Cobalt Corp] operation in the DRC [Democratic Republic of the Congo]. We can also confirm that James Bethel was the head of copper cobalt in the DRC until 30 September 2014.

“The two friends were travelling on holiday through the USA. We are awaiting further information regarding their deaths from the authorities in the USA.”

ENRC ended its controversial spell as a London-listed company in November 2013 when it was taken private by its three founders and the Kazakhstan government.

It had suffered from a series of corporate governance issues – which once saw the business labelled “more Soviet than City” – as well as numerous allegations of corruption. The claims prompted the Serious Fraud Office to launch an investigation in 2013, focusing on allegations of “fraud, bribery and corruption” in Kazakhstan and Africa. The company confirmed the investigation was still open.

After floating ENRC on the London Stock Exchange in 2007, the company’s shares were quickly propelled into the FTSE 100 and, therefore, into many British pension funds.

However, its persistent problems caused the share price to crash by 85%, prompting it to be taken private again by its three founders, Alexander Machkevitch, Patokh Chodiev and Alijan Ibragimov.