Locals in Melbourne's north-east are holding a candlelight vigil at an Alphington roundabout where two lemon-scented gum trees were cut down so a gas pipeline could be repaired.

Save Our Trees convener Helen Schapper, 65, who has lived next door to the roundabout for more than 30 years, said the community was "in mourning" after the trees were felled by APA Group.

Locals have camped out in the roundabout for more than three weeks. Credit:Alphington St Roundabout Trees/ Facebook

"It's like watching your child being hacked to death, that's what it's like," she told The Age.

Locals took turns camping out at the roundabout for more than three weeks. One woman was there when dozens of police officers arrived at 7am on Tuesday to barricade the machinery.