Google has denied claims that many Android-based phones have been infected with a virus that causes the devices to send out spam en masse, reports the BBC.

Microsoft researcher Terry Zink claimed earlier this week to have discovered evidence that Android phones have been infected to create a botnet, which generates huge amounts of spam from host devices.

Google said in a statement that there was no evidence to support the claim that Android devices sent the spam. The company’s investigation suggested that spam messages originated from PCs but were formatted to look like they were sent from Android smartphones.

"Our analysis suggests that spammers are using infected computers and a fake mobile signature to try to bypass anti-spam mechanisms in the email platform they're using," the Google statement said.

To date, there has never been a case of a botnet being created using Android phones.