Hackers took over news agency Associated Press’s Twitter account and sent a false tweet about the US president that briefly sent US markets reeling.
Amid the chaos of the US election campaign’s closing days, Ohio has become a test centre for the growing science of political advertising.
Barack Obama’s re-election campaign and Democratic allies have raised more than $68-million in the last three months, surpassing the Republicans.
US researchers must have known they were violating ethical standards by infecting Guatemalan prison inmates and mental patients with syphilis.