"It's just one of those inquiries where it's just got to be taken one step at a time."
The latest recipient of the VC, Corporal Willie Apiata, urged the public to help the police with the recovery of the medals.
He said the theft of the medals was distressing.
"The families of those who were awarded the missing medals have been robbed of a personal connection to their loved ones and New Zealand has been robbed of the link, which the stolen medals represent, to the courageous actions of all those service men and service woman who have served their country at home and overseas.
"Since being awarded the VC I have always felt that I wear it on behalf of my unit, the NZDF and New Zealand. "
Mr Mastrovich said he was sure the case would be resolved and he appealed to the offenders to give themselves up.
He also urged anyone with information about the crime to come forward to police.
"But apart from that we still want to hear from anybody who was in Waiouru late on Saturday and up until 2am on Sunday, just so we can piece together movements in the town at that time.
"So it's local residents, truckies, people passing through - anybody."
He said it was unclear how many burglars there were, but there was probably more than one.
At the moment it did not look like an inside job, Mr Mastrovich said.
"But we're just keeping an open mind about it and until the scene examination is complete and we can have a good look at what we've got we're not going to jump to any conclusions."
Police earlier said they had located a number of items which could be connected to the theft.
Mr Mastrovich says police were currently removing objects that were found on the grounds of the museum, following a grid search. He said they were looking for anything that was out of place, like pieces of material or metallic objects.
He said all the items they have found were being photographed and examined.
Police were also trying to establish the points of entry and exit from the museum, with the entire scene examination expected to take two days.
If the medals escape border control, Prime Minister Helen Clark fears the missing war medals may never be found.
The break-in is being described as an attack on the nation's heritage by the army who have set up a counselling service for museum staff.
Major Simon O'Neil has been liaising with police on the investigation and said staff were taking the break-in personally.
"They take a lot of ownership and it was very invasive," Major O'Neil said.
The Prime Minister called the crime "appalling" and "revolting", and urged the thieves to do the right thing.
"The fear is there is a very reclusive collector who has had them stolen to order," Helen Clark told One News' Breakfast program.
"If that's the case, they won't show up on the market".
Helen Clark advised the robbers to return the medals by "popping them in a letter box" where someone would inevitably find them.
Ruapehu police want to talk to anyone who was in the small North Island town between midnight on Saturday and 2am Sunday in the hope of any clues that will help identify the brazen thieves.
Police believe nine Victoria Crosses stolen in a smash-and-grab operation were targeted in a well-planned heist that could make the thieves millions of dollars on the black market.
Police say the robbery was a slick operation that had to circumvent an alarm, security cameras and patrols.
The thieves entered the museum through a fire escape at the rear of the building and went to the Valour Alcove, where gallantry medals are held in locked display cabinets of reinforced glass.
Among the medals stolen was Captain Charles Upham's medal and bar, which sold last year, reportedly for more than $1 million and was on loan to the museum.
Returned and Services Association national president Robin Klitscher said the theft was an outrage.
"There have been only 1354 VCs awarded and 22 to New Zealanders," he said.
"Their value is well beyond money. They're very hard earned, very difficult to come by and represent the best New Zealanders can do."
The museum's executive trustee, Lieutenant General (Rtd) Don McIver, said the medals would be hard to sell, as each was engraved with the name of its holder.
"But that wouldn't mean hard collectors wouldn't be prepared to have the medals, even if they couldn't display them."
Inspector Mastrovich said the thieves seemed to know what they were looking for. "They targeted the Valour Alcove. It looks as though it was well planned and well executed.
"Some material was left behind, so it looks like they possibly had an idea of what they were looking for."
Massey University associate professor of defence studies Glyn Harper said the robbery was a tragedy.
"In terms of gallantry decorations in the British Commonwealth, the VC is the highest you can get. They are extremely rare.
"I am shocked and saddened, and a little bit angry.
"It's a tragedy because the awards belong to the New Zealand nation as much as they do to the individual and their families."
He said the average value of a VC was $500,000, but the Upham medal and bar was worth "millions because it is one of only three in the world, and the only one ever awarded to a combat officer".
"But the monetary value is irrelevant. These things are priceless."
General Gardiner said security at the museum would be reviewed, but all measures - including reinforced glass, security patrols and security cameras - had worked as they should have.
Film from security cameras has been given to the police and border control authorities are on the lookout for any attempt to take the medals overseas.
National's defence spokesman, Wayne Mapp, said the theft should prompt the Government to conduct a full-scale security review of all museums carrying valuable war medals.
"Medals bestowed on our military personnel are part of our national heritage and must be safeguarded for future generations," he said.
One of Captain Upham's three daughters last night said the thieves had to be "deranged".
Amanda Upham, 59, said the family were shocked by the theft.
"It's dreadful, just horrendous. I'm horrified that anyone could do this," Ms Upham said.
Meanwhile collectors and museums holding valuable medals and memorabilia should review their security in the wake of the theft of the medals, Massey University historian Glyn Harper said.
Dr Harper said the theft from the museum bore the hallmarks of a professional burglary.
"The thieves were only there for a short time and whoever took them knew which medals to take - those most valuable to New Zealand."
Dr Harper said markets existed for stolen medals .
"There is still a black market - some people have a lot of money and not all have the ethics that preclude them from buying something stolen."
Dr Harper said the medals were a vital part of New Zealand's military heritage.
UNIQUE DOUBLE
Charles Upham's two Victoria Crosses - known as the VC and bar - were embroiled in controversy last year, when his three daughters wanted to sell them to a British collector for $3 million.
The Government insisted the medals should not leave the country, and they were sold last year for an undisclosed sum, believed to be more than $1 million, to Britain's Imperial War Museum and loaned back to New Zealand for 999 years.
They had been in the Waiouru Army Museum for a year.
Charles Upham is the only combat soldier in the history of the Victoria Cross to be awarded the medal twice.
- with NZPA, NEWSTALK ZB
Police have set up a hotline - (06) 349-0600 - for anyone with information about the theft or the medals.
