Staff at Hawke's Bay Hospital are reeling after a locked box containing money to keep their memorial garden in pristine condition was stolen.

Police are trying to track down three youths who stole the Chaplain's Remembrance Tree donation box - one even sitting in a wheelchair apparently disguising himself as a patient.

At around 5.40pm on Sunday, they were caught on camera over six minutes waiting for the entrance way to be clear of passers-by so they could grab the box and run.

Hawke's Bay District Health Board Security Manager, Rob Thorpe said, "CCTV footage of the youths inside the Hawke's Bay Hospital entrance foyer, where the remembrance tree and donation box is placed, as well as footage of the youths exiting the building with the box, has been forwarded to local police."

It was not known how much money was in the box, but it had been cleared earlier in the day.

Hawke's Bay Hospital Chaplain, Reverend Barbara Walker said to have the entire box stolen and destroyed was extremely upsetting and had "tainted the whole thing".

"We all feel quite upset about the whole thing really. This money is not for us. It goes to the memorial garden to buy some more plants, trees and roses; which is very popular among the patients, staff and families."

The tree was put up on December 1 and gave people the opportunity to give a gold coin donation and put a dove on the tree to remember their loved ones.

However, it was not the first time money had been stolen from the hospital, with the same thing happening last year, leading to an upgrade from a plastic bucket to a locked wooden box.

"One of the carpenters at the hospital made us four solid collection boxes so we had one of them out there on the table. The wood came from Napier Hospital so it holds a lot of memories for us and also for the community."

On Friday they will have a remembrance service where they collect the doves off the tree and bless them, before burning them and scattering the ashes in the garden.

Reverend Walker believed the right thing to do would be for the perpetrators to "apologise to us, the DHB and also the carpenter who actually spent hours on these boxes."

In the last nine years around $2500 had been raised with support from the palliative care group, including $350 this year alone.

"We will continue to put this out and we just hope that this will stop and the people who did this will actually think that it is not the right thing to do."

A Hawke's Bay District Health Board spokeswoman urged people to help police with their inquiries.