Washington, Jun 5 (IANS): Google has warned that Chinese and Iranian hackers are targeting both Donald Trump and Joe Biden campaigns as the US inches closer towards presidential election in November.

Hackers backed by China and Iran state agencies are sending phishing emails, attempting to steal the email credentials of campaign staffers for both major Republican and Democratic parties.

Shane Huntley, head of Google's Threat Analysis Group (TAG), tweeted on Thursday that recently, TAG saw China advanced persistent threats (APT) group targeting Biden campaign staff and Iran APT targeting Trump campaign staff with phishing.

Huntley said Google has passed the information to the federal law enforcement agencies.

"No sign of compromise. We sent users our govt attack warning and we referred to fed law enforcement," said Huntley.

In 2016, Russia-backed hackers interfered with the US election.

In a statement, the Biden campaign said Google had notified it of the attempted intrusions, reports NPR.

"We have known from the beginning of our campaign that we would be subject to such attacks and we are prepared for them. Biden for President takes cybersecurity seriously. We will remain vigilant against these threats and will ensure that the campaign's assets are secured," the Biden campaign spokesperson said in a statement.

The Trump campaign was yet to respond to Google notification.

Government-backed phishing has been in the news lately. One of the main threats to all email users is phishing, attempts to trick people into providing a password that an attacker can use to sign into their account.

"Our improving technology has enabled us to significantly decrease the volume of phishing emails that get through to our users. Automated protections, account security (like security keys), and specialized warnings give Gmail users industry-leading security," Google said in a statement.