The City of Edmonton has apologized for taking down more than 1,000 handmade paper hearts hung from trees in a healing forest to honour residential school survivors.

The colourful hearts with messages of love and support written by Edmontonians lined the woodland by River Valley Road between Groat Road and the High Level Bridge.

Parks officials said Thursday the hearts were taken down by a two-person trails crew who didn't realize their significance.

"It's really unfortunate, our trails crew feels really poorly about the situation and we're reaching out to the group," said Travis Kennedy, acting director of parks operations for the northeast district.

Volunteers are upset the hearts they hung in November along a river-valley path have been taken down. (CBC News) Volunteers with the group Reconciliation in Solidarity Edmonton (RISE) spent several hours hanging the hearts on the trees last November.

On Wednesday, a member of the group noticed they were all gone.

Kennedy said the city crew that was responsible was in the area doing pruning work on the morning of Feb. 23.

They noticed some paper hearts on the ground and a few snagged in plants and thought the area looked untidy.

Without calling for clearance, they picked up the hearts on the ground and removed all the remaining ones from the trees as well.

"They likely should have touched base with the crew leader," Kennedy said.

He described what happened as a misunderstanding, a mistake not by the crew but by their supervisors, who should have been more clear about how meaningful the hearts were.

To make matters worse, the hearts were taken to the landfill.

"I can't believe they're all thrown out," said Sara Komarnisky, who leads the volunteer group behind the project. "I mean, thinking of these beautiful messages going to the landfill, it's really heartbreaking."

The hearts were made at a series of events to honour residential school survivor, Indigenous children in care and missing and murdered Indigenous women.

Sara Komarnisky, right, is disappointed the city removed the hearts and sent them to the landfill. (CBC News) Initially, they were placed outside city hall, where they made up a heart garden. They were later moved to River Valley Road.

Juanita Spence, supervisor of river valley parks and facilities, said the city will apologize to RISE and offer to work on a permanent memorial in the area.

Spence said the city's Indigenous relations office will be involved.

"I just found out about this so it will be good to talk to them and see what they have to say," Komarnisky said. "I'm open to the conversation and I'm glad to know what happened, even if it is really very sad."

Komarnisky said it's too early to know if she can accept the apology, because she's still coming to grips with the news that so much hard work has disappeared.