(COMBO) This combination of file photos created on July 15, 2020 shows (L-R, top to bottom) Microsoft founder Bill Gates in Lyon, France, on October 9, 2019; Democratic presidential candidate Joe Biden in Wilmington, Delaware on July 14, 2020; SpaceX founder Elon Musk in Washington, DC, on March 09, 2020; and Blue Origin founder Jeff Bezos in Washington, DC, on October 22, 2019. - The official Twitter accounts of Gates, Biden, Musk, Bezos and other high-profile accounts were hijacked on July 15, 2020, by scammers trying to dupe people into sending cryptocurrency bitcoin in the hope of doubling their money. Posts, which were largely deleted, were fired off from the array of accounts telling people they had 30 minutes to send $1,000 in bitcoin in order to be sent back twice as much. (Photos by AFP)