problem with folder servor

Hello,
I take over a client’s site, and he was probably hacked. I started to set up a security system with the htaccess, itheme security, CHMOD … I launched a scan from the back office with Anti malware, and, for the moment, anlysis find me malicious scripts, in a phpmyadmin directory at the root of the site. I’m afraid of the risk that this can cause by removing his scripts in this directory. The fact that it is PhpMyadmin brakes me a little. Is it normal to have this directory at the root of my site? Is it normal to have a Generator directory at the root? I can not contact the old webmaster anymore so I am a bit in the dark. The scan finds me malicious scripts of the type:
– … / httpdocs / phpmyadmin / js / openlayers / src / openlayers / lib / Firebug / firebug.js
– … / httpdocs / phpmyadmin / js / jqplot / jquery.jqplot.js
–
… / httpdocs / phpMyAdmin / js / function.js
Thanks for your help !
cordially
Nicolas