Case insensitive match

"Faine, Mark R. (MSFC-IS40)[NICS]" <[email protected]> Mon, 7 Dec 2020 17:01:41 +0000

Newsgroups	gmane.comp.monitoring.monit.general
Message-ID	<SA0PR09MB62522C1C835A748C5C01977DE9CE0@SA0PR09MB6252.namprd09.prod.outlook.com>

I have this regex I'd like to match but I need "error" to be case insensitive:

.*syslog-ng\[[0-9]{1,5}\]:\s+(?<!I\/O)(error.*)

Also, is negative look behind supported?

Thanks,
-Mark