Detainers are requests filed by ICE for local jurisdictions to keep in custody illegal immigrants who have been arrested on criminal charges and are believed to be "removable."

Detainers are requests by federal immigration enforcement for local jurisdictions to keep in custody immigrants who have been arrested on criminal charges and are believed to be "removable."

Prosecutors are pushing to keep in custody five people arrested in the U.S. this week for their alleged roles trading on corporate earnings information stolen from newswire companies by suspected hackers in Ukraine.

One of the men Brooklyn prosecutors want to keep in custody is Vitaly Korchevsky, 50, who is being held at a federal prison in Philadelphia.

In future, police will not honor any request to keep in custody jailed immigrants - including those arrested for violent crimes - unless the request comes from a judge, Neiman said.