The owner of an antique shop where the razors were bought for a school play said the person who purchased them had talked to one of his staff members about the need to cover up the sharp edge.
The man, who asked the Herald not to be named, said he believed the person was a teacher at St Kentigern College, "a really nice chap," who said the razors were going to be used in a production of Sweeney Todd.
Two pupils of the school were taken to hospital last night with cuts to their throats suffered during the production.
The owner could not immediately recall whether the man had mentioned it would be a high school production.
"I know they discussed the safety element and maybe covering up the blade."
The two blades, which retail for about $40 or so, were bought a couple of months ago the man said.
When the staff member who sold the razors heard what had happened this morning she was quite upset, but the sale of cut throat razors was not unusual and they had been sold to an adult, the man said.
The man said he sold a lot of cut throat razors, especially with the popularity of single blade shaving increasing recently, and said he "never would have thought" this would happen.
"You can sell someone a brick and if they drop it on their foot you would still feel sorry for them."
St Kentigern College head Steve Cole says two the boys' whose necks were cut with a prop razor during last night's opening performance were out of hospital and doing well.
In an interview with Newstalk ZB's Larry Williams, Mr Cole explained the "unfortunate" incident happened halfway through the performance's second act.
The prop was a razor which had been blunted and wrapped in several protective layers, Mr Cole said.
"It's normal for Sweeney Todd to have such an instrument [and it] clearly had been checked many, many times.
"It has been bound and cellophaned and all sorts of things. It had been blunted and had been through all sorts of health and safety checks. It was a very unfortunate mistake."
The scene had been performed "many times" since January including eight dress rehearsals where the prop was used.
When asked how two boys ended up with the sides of their necks cut last night, Mr Cole said he didn't know.
"I've got no idea. I've got no idea."
Mr Cole said he understand the boys had been discharged and were doing well.
He was not concerned about possible consequences for the school under new health and safety laws which came into force on Monday.
"I've given that no thought at all. We're very confident in our health and safety procedures. My concern is for the two boys and their families."
Tonight's play was still postponed but Mr Cole said he hoped the rest of the show's run would still ruin - "without those particular props."
Mr Cole told TVNZ this afternoon the prop was covered "in all sorts of duct tape and foam and silver paper."
"It was a razor that you would expect to see in a production of Sweeney Todd. But it didn't have a sharp edge. I'm very confident that the health and safety situation was strong," he said.
"It was an unfortunate isolated incident."
He said it was not unknown for schools to use props like this, adding the razor's edge had been filed down and bound.
Mr Cole said in hindsight it may have been a better idea to eliminate all risk, but said the drama students involved had been adamant the play look at authentic as possible.
"It was chosen because of the very nature of the talented young men and women we have in year 12 and 13 who wanted something that would push their skills and the boundaries.
"It was deemed important to make it as realistic as possible."
The Auckland private school has put on hold its production.
Detectives are investigating what caused the two 16-year-old boys at Saint Kentigern College to suffer cuts to their necks while on stage.
The boys were taken to Auckland City Hospital last night, one with serious injuries. They are in a stable condition and it has been reported that they will likely be discharged today.
Police arrived at the school and helped with inquiries into the incident. He said there was nothing to indicate anything untoward took place on stage. "It's not a criminal inquiry. In this instance the play is not the reality," said the police spokesman.
Mr Cole saying they were supporting the injured boys. "Our priority is to support the boys and their families, along with the rest of the cast and crew," Mr Cole said in a statement.
"We are distressed about what happened last night and are conducting a thorough investigation. We are pleased that both boys are in a stable condition and have been talking with both their families."
Mr Cole said plays and performances were a big part of the school's life. He had been in meetings all morning with management over the incident.
The musical, by Stephen Sondheim, features cut-throat razors and in pictures of the production the members of the show's cast can be seen using them. The school told the Herald that tonight's performance had been put on hold.
The Ministry of Education has offered its support to those at the college. Head of Sector Enablement and Support Katrina Casey said they'd contacted the school to offer any support its members required during "this clearly difficult time".
"We are sorry to hear about the incident that took place there last night."
WorkSafe New Zealand is looking into the incident at the college.
"The initial notification to WorkSafe advised that two boys had received neck injuries while enacting a scene in a musical production."
Some people connected to the college are saying the teenage boys were injured on stage by the sharp blade of a cut-throat razor prop, while others speculate they may have been injured leaving the stage through a trap door chute.
During the busy drop-off period this morning, most parents spoken to by the Herald were unaware of what had happened last night - with several saying they had only heard about the incident in the media this morning.
During the show, Sweeney Todd's victims are cleanly dispatched from the barber chair. The school website says the set design was in keeping with the Broadway version which included a revolving stage.
It also faced the challenge of creating a mechanical chair to dispose of Todd's victims directly down a chute into the bakehouse.
Trust board member Dr John Kernohan confirmed the musical Sweeney Todd was being held at the school. He said he left the production at about 10pm and was not aware of an incident occurring. The school's head of music Ross Gerritson wouldn't comment.
The show re-tells the Victorian melodrama of Sweeney Todd, an English barber and serial killer who kills his customers with a razor and, with the help of Mrs Lovett, a struggling pie shop owner, turns their corpses into meat pies. The musical was made into a hit film starring Johnny Depp and Helena Bonham Carter.
St Kentigern College is a private independent Presbyterian day and boarding school offering education for girls and boys aged 11 to 18 years.
The large secondary school is set on the banks of the Tamaki Estuary in Pakuranga.
It boasts extensive playing fields, world-class learning facilities and park-like settings.
Parents are charged $19,625 a year in tuition costs for their children.
It costs an additional $14,920.00 to board.
The college is divided into a middle and senior school. Pupils are taught separately in the junior level but classes are co-ed in the senior years.
Pupils have a choice of gaining either the International Baccalaureate Diploma or NCEA.
It is described on its website as a contemporary, state-of-the-art, educational facility which remains true to its traditional Christian faith, values and Scottish heritage.