US authorities have arrested Hong Kong's former home affairs secretary and the ex-foreign minister of Senegal for leading a multimillion dollar bribery scheme in Africa on behalf of a top Chinese energy company, with some deals arranged in the halls of the United Nations.

US officials announced Monday that former Senegalese top diplomat Cheikh Gadio and Hong Kong's Patrick Chi Ping Ho sent huge bribes to high-level officials in Chad and Uganda to secure business advantages for the Chinese company.

The company was not identified in the announcement or the complaint filed in New York federal district court, but details in the complaint pointed to CEFC China Energy, the Shanghai-based rising star of China's energy industry.

CEFC China Energy has blown onto the scene in just a few years, taking major stakes in global projects, including a 14 percent chunk of Russia's Rosneft, and playing an important role in Chinese President Xi Jinping's ambitious One Belt One Road initiative.

In the Justice Department complaint, the two men allegedly offered a $2 million bribe to the president of Chad "to obtain valuable oil rights," and a $500,000 bribe to an account designated by the Minister of Foreign Affairs of Uganda, who had recently completed his term as the President of the UN General Assembly.

"In an international corruption scheme that spanned the globe, Chi Ping Patrick Ho and Cheikh Gadio allegedly conspired to bribe African government officials on behalf of a Chinese energy conglomerate," acting Manhattan US Attorney Joon Kim said in a statement.

The charges were based on their use of the US banking system to process almost a million dollars in payoffs, sent under the guise of donations.

Ho, who led a Hong Kong-based organization called the China Energy Fund Committee, also known as CEFC and funded by CEFC China Energy, also provided Uganda's president and foreign minister with gifts and promises of future benefits -- including a share in the profits of a potential joint venture, authorities said.

"Their bribes and corrupt acts hurt our economy and undermine confidence in the free marketplace," said Acting Assistant Attorney General Kenneth Blanco. 

Ho, 68, and Gadio, 61, are each charged with violating the Foreign Corrupt Practices Act and money laundering, with possible jail sentences of as much as 20 years. They were arrested over the weekend in New York.

Ho was Hong Kong Home Affairs secretary from 2002 to 2007, and severed for several years on the  Chinese People's Political Consultative Committee Conference.

Gadio was Senegal's foreign minister from 2000 to 2009.

CEFC China Energy's role was apparent in the formal complaint. It identified the chairman of the unnamed company as someone who was appointed as a "special honorary advisor" to the president of the UN General Assembly in 2015, when Ugandan Foreign Minister Sam Kutesa held that position.

A Chinese media report at the time showed CEFC China Energy Chairman Ye Jianming together with Kutesa noting Ye had just been named a "special honorary advisor" to the UN General Assembly.

Ye was labelled China's "newest oil baron" by Forbes magazine in 2016 after his company made a number of large investments in the Czech Republic.

CEFC China Energy has spread its business through Eastern Europe, Africa, and the Gulf states, rising in just a few years to be a major player in world oil markets and raising questions about its backing inside China