The two burglaries happened in the early hours of Friday morning, between 1.30am and 2.30am, in Downer. In both cases police said the intruders gained entry to homes through unlocked back doors while the residents slept.

While no one was harmed in either burglary, thieves took a number of small items from each home, including a mobile phone, a wallet, and handbags.

Acting Superintendent Bob Wynn said open windows and unlocked doors catching cool breezes in the summer months were a beacon for opportunistic criminals.

He said while there were no obvious peaks or troughs in crime stats between winter and summer, the change of seasons required extra vigilance from Canberra residents.

“Certainly with the warmer months, people in general are out and about more. So it would stand to reason that people who are looking to commit crime are also out and about,” he said.

“I guess you could argue that there is a seasonal aspect to crime, particularly burglaries and thefts, where during the summer months people tend to have their doors and windows opened – in other words, unsecured.

“People that break into houses and steal things, they’re very much opportunistic. So if they see an open window as opposed to a closed window, well they’re going to go the easy line and break in through the open window.”

Detective Wynn recommended people invest in security locks which allowed windows to be locked open a small amount, letting in breeze but keeping out crooks.

He said summertime holidaymakers should ask neighbours for help to ensure homes didn’t look empty – lights on timers, cars moved in the driveway, mail checked and newspaper deliveries cancelled all helped a house looked lived in and would deter opportunistic thieves.

And with busy summer events already underway, Detective Wynn said it was also important to remain vigilant and keep personal items and bags secured when in large crowds of people.

“The reality is, summertime brings people out … any area tends to be a little bit busier in the summer months,” he said. “Crime prevention is the best measure.”

In an unrelated incident, a man was robbed at knifepoint while withdrawing money from an ATM at Hawker shops about 9.45pm on Saturday night. The victim handed over cash, and the offender ran from the scene.

The offender is described as Middle Eastern in appearance and about 170-175 centimetres tall. He was wearing a long sleeved blue shirt, white balaclava, gloves and dark pants.

Anyone who may have witnessed suspicious activity in the Downer area last Friday or in the Hawker area on Saturday night is urged to contact Crime Stoppers on 1800 333 000 or via the website. Information can be provided anonymously.