Help with javascript malware

Hackers have injected javascript malware into my WP installation.

When viewed with Safari, some code that includes data:text/html,<script>window.close();</script> is executed, and the browser is redirected to a page that displays a pop-up which reappears when closed. This pop-up contains an alarming message trying to get the user to call a phone number. When viewed in Chrome, a new tab is opened, which prompts the user to download some software.

I’ve installed and ran a number of malware scanners including Sucuri Security, WordFence, Quttera Web Malware Scanner, and Exploit Scanner. None of them found anything.

Any ideas ?