New Zealand police say they've arrested a 33-year-old man after they found ammunition and a package containing a suspected explosive device at a vacant property in Christchurch.

The city is where a gunman killed 50 people at two mosques on March 15. Police said at the time that the gunman had a number of weapons as well as two improvised explosive devices in his car. Police have not yet said whether they think the latest incident has any link with the March attack.

Police Superintendent John Price said in a statement Tuesday that a defense force bomb squad had rendered the package safe.

Police evacuated a number of nearby houses and temporarily imposed a no-fly zone as the incident unfolded. They were removing the cordons Tuesday evening.