Thousands of New Zealanders took part in an emotional ceremony Wednesday to mark the one-year anniversary of a powerful earthquake that left 185 people dead in downtown Christchurch.

The names of the victims were read in the city's North Hagley Park before tearful mourners observed two minutes of silence at the exact moment when the quake struck.

The ceremony ended with the release of 185 Monarch butterflies, meant to represent the departed souls of the victims and the rebirth of the city. New Zealand Governor-General Jerry Mateparae said he is confident the city can rebuild.

“Like the life cycle of the butterfly, from the shattered cocoon of a once-great place, a new and vibrant city can arise. It will be a city and a region inhabited by a resilient people and built on the foundations of a strong community.”

The 6.1 magnitude earthquake destroyed thousands of homes and other buildings in downtown Christchurch, causing $25 billion in damage and turning the downtown area of New Zealand's third largest city into a virtual wasteland. Many of the victims were language students from across Asia who died when their school building collapsed.

A number of Christchurch residents have complained about the slow pace of recovery. Christchurch Mayor Bob Parker acknowledged there is still work to be done, but called on the city to come together to finish the process.

“It's still a difficult time and we acknowledge that. There are many unknowns. There are questions still to be answered, suburbs to be rebuilt, a city to be rebuilt. The 22nd of February is a day that changed things for us in this province and this city irrevocably. We can never be the same again.”

Prime Minister John Key said February 22 will be remembered as one of the darkest days in the nation's history, but also one on which the best of the human spirit was on display.