Older comments from OJS 2.4.5

Hello,

OJS 3.0.2

In our multijournal OJS there was a journal that had a considerable activity regarding the users comments in the articles. When upgrading to 3.0.2 those comments stopped being displayed and available and some entries in PHP error_log pop up regularly because of crawling those links that don’t exist anymore.
But now I want to get rid of them totally. Should I delete the entries in the comments table (and others) or what procedure you suggest being more accurate for this purpose?

Thank you for your time and effort,
Best regards