The woman, accompanied by a friend, was changing her four-month-old’s nappy in the change rooms on the lowest level of Dubbo Square on Monday afternoon when a man and woman walked in.

The pair had a cup with a powder in it and appeared to add water to it before using syringes to inject a substance, the horrified mother said.

She changed her daughter’s nappy as quickly as possible so they could leave before any trouble. She said she found their behaviour unnerving.

“The female smiled at us when she walked in and she kept staring at us but the man acted like we didn’t exist,” the concerned mother said.

“They whipped out these syringes and started using them in front of us.”

“I was just trying to get out of there as quick as possible. I was worried they might get angry we were there or want our wallets.”

On Tuesday morning she reported the incident to management at Dubbo Square.

“I gave a description to centre management and they urged me to contact the police and report it, which I did,” the mother said.

“I have heard stories about people using change rooms and be interrupted by people wanting to do drugs but I have never seen anything like it myself.”

A spokesperson for Dubbo Square centre management said the matter was being treated seriously.

"Like the community, we are concerned about the reported incident at Dubbo Square and we have a zero tolerance towards all anti-social behaviour,” the spokesperson said.

“We have actively responded to the incident that was reported to our centre management office and we are continuing to work with police and provide ongoing security to ensure that Dubbo Square remains a safe and enjoyable place for the community, our retailers and the people who come to work here each day."

Orana Local Area Command Acting Commander Scott Tanner said police had zero tolerance for drug use in a public place and urged anyone who witnessed it to contact police.

“Anyone injecting in a public place is putting lives at risk, including their own,” Acting Superintendent Tanner said.

“If people choose to take drugs in their own home, that’s one thing but doing it somewhere like a shopping centre, and in the presence of young children, is disgraceful.

“Police have no tolerance for that and nobody else should either. Anyone who sees it should report it to police and we will do everything in our power to identify those involved and catch them.”

If anyone sees anything suspicious they can report it to Dubbo police by calling 6883 1599.