It appeared that tweets posted on Dorsey's account by the hacker were up for about a half-hour before they were removed.
"Confidential information regarding 14,200 individuals diagnosed with HIV up to January 2013 is in the possession of an unauthorised person."
Nearly 10,000 people reported being victims of this kind of fraud in 2017 with losses over $56 million, an FBI report shows.
Facebook admits that up to 87 million users may have had their data hijacked by Cambridge Analytica.
The two founders of the Mabna Institute were among the 10 people whose assets are subject to US seizure, it said.
"This is something that we don't have today: a trusted international organisation for cyber-attribution."
NHS, the world's fifth-largest employer, with 1.7 million staff, was badly hit, with around 45 facilities affected.
"The recent attack is at an unprecedented level and will require a complex international investigation to identify the culprits," says Europol.
Trump has repeatedly denounced as "fake news" the accusations that members of his circle coordinated or colluded with Russian officials.
Nsale was arrested last Friday together with a Kenyan national.
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