An Auckland woman says her son is terrified of taking the bus after being threatened by two boys with a machete at Albany Bus Station on Monday afternoon.

The woman, who did not want to be named, said her 17-year-old son had just seen a friend off on a bus, when two youths stood over him, threatening him in an attempt to steal his shoes.

"He'd felt this sharp thing go into the side of leg, into his jeans, and he didn't know really what it was. And he looked up, and there were two youths, on either side of him. He looked up at them and they said, 'give me your shoes'. And he said 'oh nah nah, please leave me alone'."

She said the boys challenged him to a fight.

"One of the kids had pulled out this big machete at him, and said 'you want a scrap, you want a fight, give me your shoes'," she recounted.

There was no security present at the station, and her son fled to a nearby mall for safety, where she was able to pick him up, she said.

Police confirmed two 13-year-olds were arrested at an Albany bus station after a group threatened a person with a weapon, shortly before 2pm.

Police said the youths had been referred to youth aid.

Auckland Transport general manager of public transport operations Rachel Cara said there was 24/7 security patrolling at Albany Station.

"Firstly, we were appalled to hear about this disturbing incident. The Auckland Transport Operations Centre was alerted by Police of the incident and the relevant CCTV footage has been saved. The Northern Busway (including Albany Station) always has 24/7 security patrolling the station, in addition to Transport Officers on site to patrol," she said in a statement.

But the woman said there was no one there when her son was threatened.

"If they'd had that same security in place that they have on school days, on a public holiday, then what happened to my son might not have happened. That's the first thing my son said - 'oh Mum, there was no-one there, just a cleaner'," she said.

She said her son would be avoiding the bus station from now on.

"I'm a solo mum, on a benefit, he worked hard to get his new shoes, and to have these two punks come and try take them off him. He'd only had them for two days."

She said threats and assaults on public transport routes were becoming more common.

"It just happens so frequently. It's just getting worse and getting worse and getting worse."