Google denies 'Android hijacked by botnet' claim

London -  Internet search giant Google has denied claims that many smartphones using its Android operating system have been hacked by an illegal botnet.

Microsoft researcher Terry Zink had claimed that there was evidence of spam being sent from Yahoo mail servers by Android devices.

Botnets typically use infected PCs as spam generators, but Zink said he found evidence that Android smartphones were being used in the same way.

Google, however, said there was no evidence to support Zink's claim, the BBC reports.

The firm said the junk messages originated on PCs, but the spammers sending them formatted them to look like they came 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," Google said in a  statement.

In a follow-up to his original post, Zink had agreed that it was not proven that Android phones had been compromised.

He added that it was 'entirely possible' that the spammers had faked the message formatting to make it look like it originated on a phone.

Zink, however, there was no doubt that the number of malicious programs written for Android was on the increase.