Shares in Atlas Mara, a company founded by ex-Barclays chief executive Bob Diamond to buy African banks, fell to a record low on Wednesday as concerns over Nigerian banks spread.

The investment firm, which Diamond co-owns with with entrepreneur and Africa’s youngest billionaire Ashish J. Thakkar, has shed 66 percent of its share value since it listed on the London Stock Exchange in December 2013, Bloomberg reported.

Concern is growing over the stability of Nigeria’s banking sector after the Central Bank of Nigeria (CBN) announced last week that it had taken over management of the country’s eighth largest commercial bank, Skye Bank, over what it said were consistent breach of cash liquidity ratios by the lender. The regulator further disclosed that “one or two other” banks were showing signs of distress.

Atlas Mara owns at least 21 percent of Lagos-based Union Bank Nigeria, whose shares have dropped almost 10 percent since the CBN announcement on July 4.

“There’s a definite link between Atlas Mara and the Nigerian banking sector,” Pabina Yinkere, an  analyst at Vetiva Capital Management, told Bloomberg.

“It’s the contagion. The Nigerian banking sector is taking strain. The negativity in the share price is linked to what we’re seeing in Nigerian banks.”

Diamond’s company paid about $270 million to increase its stake in Union Bank in September 2014, a bank that was bailed out by regulators in the West African nation to stop it from collapsing amid a global financial crisis.

In a stress-test conducted by CBN in the first quarterd of this year, Union Bank had a capital adequacy ration of 15.4 percent, barely above the minimum requirement of 15 percent.

While authorities in Nigeria have maintained that banks are not in distress at the moment, there has been an increase in unpaid loans as Africa’s largest economy stare at a possible recession dragged down by a tumbling local currency and low oil prices on the international markets.

The downturn in commodity prices has battered many African currencies, slowed some economies and forced change in the banking sector.

Several other multinational banks on the continent, including Barclays and Ecobank,  have indicated their intentions to scale back or spin off their units across Africa, something analysts say is a sign of changing fortune for the banking sector on the continent.

While the trend seem to be changing for many multinational lenders in Africa, others such as Standard Chartered Bank and Diamond’s investment vehicle Atlas Mara are still seeking to grow their presence on the continent.

For Atlas Mara, which aims to become one of the top banking sector players in Africa, the commodities downturn in Africa offers an opportunity to acquire more banks on the continent.

The investment firm already operates in seven sub-Saharan Africa countries including Rwanda, Nigeria, Botswana and Zimbabwe, and targets about 14 countries in Africa where it wants to establish its footprint.