A judge ruled New York City is now in contempt over "grave" conditions at the Rikers Island prison complex, with a federal takeover of the system now seen increasingly as likely in a years-long legal battle.

The finding was a landmark in a court case that has stretched out over more than a decade. Plans for a receivership of New York City’s jails will be heard on Jan. 14.

A U.S. judge on Wednesday said she was leaning toward ordering a federal takeover of New York City's Rikers Island jail complex, after finding the city had failed to improve violent conditions that put inmates and staff at risk.