People who use social networks are posting personal information that could be used by professional home burglars looking for potential targets, a study released last week found.

Nearly four in 10 people using sites such as Facebook and Twitter have posted specifics on holiday plans and a third have offered status updates during a weekend getaway, according to the Digital Criminal report prepared by the U.K. financial services company Legal & General. Coupled with the fact that a high proportion of people often agree to be online "friends" with strangers, the easily accessed personal information increases the risk of home break-ins.

Of 100 "friend" or "follow" requests issued to strangers selected at random, 13 percent were accepted on Facebook and 92 percent on Twitter, without any checks. In addition, 17 percent of users surveyed for the study reported seeing people's residential addresses posted on pages that could be seen by strangers.

Such carelessness could easily lead to strangers discovering a person's interests, location, and movements in and out of their home, the report said.

"There is absolutely no doubt in my mind that burglars are using social networks to develop relationships with people to identify likely targets," Michael Fraser, a reformed burglar and star of the BBC's Beat The Burglar series, said in a statement. "They gain confidence by learning more about them, what they are likely to own and when they are likely to be out of the house, and then target appropriate victims."

Fraser, who helped in the development of the report, said that burglars can easily use the information gathered on social networks to choose their victims, and then scope out more information on their homes through other websites, such as Google Street View. "It scares me to see how many people are prepared to give away valuable information about themselves, to people they simply don't know well enough—if at all," he said.

In looking at how people meet strangers on social networks, the study found that 79 percent of people using the sites believe they are a great way to track down people they "met on holiday," three quarters said it was a good way to meet "friends of friends," and nearly half like to use the sites to meet people based only on them having a nice picture.

"In just one week, a professional burglar, or a team, can use social networking sites to harvest dozens of potential targets," Fraser said.

New users of Facebook, for example, are key targets, because they are keen to build up their number of "friends" or "followers," the ex-burglar said. Pet owners are also good targets because they often depend on their dog for security, and are lax in taking other security measures. Cat owners often have weakened back doors because of the use of cat flaps, and pet owners in general tend to turn off alarms.