<?php namespace MyNamespace;
    include 'IpSpecsApi.php';

    $fnameIpSpecsDb = 'IpSpecsHighFraudRisk.dat';
    $ip = '65.32.65.22';
    if( IpSpecsMatched($fnameIpSpecsDb, $ip) ) {
        // flag user
    } else {
        // user is clean
    }
?>

Download library: http://www.ipspecs.com/download/api_php.zip