A Microsoft researcher has claimed that smartphones running Google's Android software have been hacked by an illegal botnet.
Whilst Microsoft's own operating software - Windows Phone, is a key competitor to Android, researcher Terry Zink make the claim, stating there was evidence of spam being sent from Yahoo mail servers used by Android devices.
The claims are another blow to Google and its platform which has had to deal with a number of issue recently, including a number of malware infected apps.
The software's official app store - Google Play - has suffered from a number of issues such as an influx of fake apps, which are commonly pirated versions of popular paid products including Angry Birds and Fruit Ninja, which are distributed for free.
Mr Zink wrote in a blog post: "A spammer has control of a bonnet that lives on Android devices."
"These devices login to the user's Yahoo Mail account and send spam." the post continues.
When questioned by the BBC on the issue, Google stressed it was working to improve security on the Android platform.
"We are committed to providing a secure experience for consumers in Google Play, and in fact our data shows between the first and second halves of 2011, we saw a 40% decrease in the number of potentially malicious downloads from Google Play," said a spokesperson.
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