A man has been arrested in connection with an offensive Facebook page set up following the deaths of police officers Nicola Hughes and Fiona Bone, Greater Manchester Police has said.
More top news
Political parties across the country suspended their General Election campaigns following the Manchester Arena terror attack on Monday.
Investigators believe Mr Kushner has significant information relevant to their inquiry, officials told NBC News.
The men were detained as part of an investigation by MI5 and the Metropolitan Police's Counter Terrorism Command.