ANDROID users are finding themselves under attack by malicious software called ransomware.
National Mobile Phone Repair director Gary Finlay said the ransomware locked down the device and demanded a $200 ransom for the unlock.
At least 12 people had brought in phones infected with ransomware in the last two weeks in the Mackay store alone.
Related link: How to fix your phone
"The ransomware we've seen lately basically accuses the (user) of viewing certain types of files, images," Mr Finlay said.
The malicious software, which was like a virus, accessed data in your phone and displayed personal information such as your full name, location, network and email address on a main page that appeared on the user's phone, he said.
"The main screen... displays some pretty scary messages about what sort of stuff has been viewed and also grabs a couple of different contacts from your phone and says that these contacts can be called up and interrogated as witnesses for your crime," Mr Finlay said.
"It does look believable. All the images are high resolution and it's got the Australian Federal Police logo.
"But when you stop and think about it there's no way you would be offered a $200 way out if you were guilty of something like that."
There is a way to stop it.
Mr Finlay said Android users should avoid installing software from untrusted sources.
"Just be careful about what sort of pages you visit on the internet," he said.
The malicious software can be attached to a variety of different websites.
"Sometimes pornography websites can be the reason why (the device) is infected," Mr Finlay said.
Other time the ransomware might be bundled with other software or certain sites such as free game sites and can sneak on to your phone that way, he said.
There are a number of ways to remove the software.
The drastic option was to "just wipe your phone" and start again, Mr Finlay said.
"You can start the phone in safe mode and remove the malicious file from there or just restore it from a previous back up on your phone," he said.
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