The combined number of incidents rose to 1,389, already topping 2014's 1,361 and reaching half of last year's total of 2,748.

The total malware and phishing incidents was 1,206 in January, up from 254 a year earlier. The IRS says the trend continue in February, nearly doubling incidents reported in February 2015. From February 1 through 16, there were 363 incidents compared to 201 for the entire month last year.

Tax professionals are reporting phishing scams that seek their online credentials to services, such as the IRS Tax Professional PTIN System.

IRS Commissioner John Koskinen urged taxpayers to "Watch out for fraudsters slipping these official-looking emails into inboxes, trying to confuse people at the very time they work on their taxes. We urge people not to click on these emails."

Bogus emails attempt to trick taxpayers into believing they are official communications from the IRS or others in the tax industry, such as tax software companies. E-mails often seek information related to refunds, filing status, confirming personal information, ordering transcripts and verifying PIN information.