Fraudsters are targeting people claiming tax credits with scam emails, websites and text messages in the run up to the July 31 renewals deadline, the taxman is warning.

Nearly 51,000 scam "phishing" emails were reported to HM Revenue and Customs (HMRC) between April and July 2014, which is double the number reported during the same period in 2013.

Some scam messages claim to be from a "tax credit office agent", offering a tax refund, or include a link to a fake version of the gov.uk website.

The messages try to trick people into giving personal information such as bank details and passwords - and fraudsters will then try to take money from their account or sell their identities to other criminals.

HMRC will never use texts or emails to tell someone about a tax rebate or penalty or ask for personal or payment information.

Last year, HMRC worked with other bodies to shut down 8,877 scam websites, marking a 500% increase compared with 2013.

Nick Lodge, director general of benefits and credits at HMRC, said: "HMRC will never ask people to disclose personal information by email. We have cracked down on phishing emails and scam websites, but the fraudsters' methods are constantly changing, so people must remain vigilant.

"The only way to renew tax credits and report changes online is on gov.uk."

HMRC has tips on how to spot scam emails at www.gov.uk/dealing-with-hmrc/phishing-scams.

If someone receives a suspect email they can forward it to phishing@hmrc.gsi.gov.uk.