Cologne authorities say they're planning to fence off a large area around the city's famous cathedral this New Year's Eve as part of stepped-up security precautions aimed at preventing a repeat of last year's attacks.

Mayor Henriette Reker said Wednesday that entry into the secure zone would only be through checkpoints, and no fireworks would be allowed, the dpa news agency reported.

In addition, police chief Juergen Mathies said there would be a strongly increased police presence both in the secure area and elsewhere in downtown Cologne.

It was outside the cathedral and by the nearby train station that most of the string of robberies and sexual assaults occurred last New Year's, blamed largely on foreign men.

That sparked a debate about immigration in Germany.