A local council is investigating the alleged illegal destruction of several trees that has left a “big scar” on a historic green wedge suburb on Melbourne’s outskirts.

Nillumbik Shire council has confirmed it is consulting lawyers over the removal of native vegetation at a building development site in Diamond Street, Eltham, that may have been contrary to a ruling from the Victorian Civil and Administrative Tribunal.

The original building permit for three new dwellings and subdivisions on the site was rejected by the council, but successfully appealed at VCAT in 2013 with a number of conditions, including a “tree protection zone” to ensure the native trees were retained.

But locals, who spoke on condition of anonymity, say nearly all of these protected trees were cut down late last week by developers.

“A number of those trees were supposed to be left – it wasn’t an accident,” a local said. “It’s just like a big scar when you walk past now. There’s only one big tree in the middle now and it was previously very filtered. It’s very, very un-Eltham and it has affected everyone’s amenity.”

Council officers have completed an investigation into the case and are now consulting with lawyers, Nillumbik Shire mayor Peter Clarke said.

“The council is taking this matter very seriously and we have referred the outcome of our investigation to our lawyers to determine what our legal options are,” Cr Clarke said.

Eltham, a small suburb 20 kilometres from the Melbourne CBD, is part of the renowned “green wedge” suburbs which have remained relatively under-developed and managed to retain tree-lined streets and leafy reserves.

Known as the “lungs of Melbourne”, Eltham locals say the leafy pockets define the suburb’s character.

“It’s quite a unique area of Melbourne,” a local said. “People come here because it has the bushy feel but it’s only 20 kilometres from the city.”

But locals are concerned that the recent loss of these native trees, along with new building developments, will threaten the character and heritage of the sleepy suburb.

“It would just become an ordinary suburb if there were large-scale tree removal,” Eltham District History Society secretary Russell Yeoman, who has lived in Eltham for more than 30 years, said. “It would significantly alter the character of the area. It’s always a battle when people are developing land for multi-units to get them to keep the trees.”

The area where the alleged illegal removal of trees has occurred is also of particular cultural importance to the locals.

“Diamond Street is considered to be quintessentially Eltham,” Mr Yeoman said. “It’s an area that has better tree cover than others, interesting architecture, mud-brick buildings and several unmade roads. It’s an area considered to be of special character.”

With the trees now lost, locals are hoping for a significant punishment to further deter other developers from destroying the suburb’s native vegetation and cultural character.

“We’re hanging on some severe penalties on whoever has done it,” a local said. “Someone is going to have to pay.”