Linux: cPanel queued mail stop

I got a serious mistake: I have a cronjob to send bulk email to my customers, but accidentally it worked and now some of our customers recieving the mails, I already deleted the cron job and deleted the mail function codes and deleted SMTP the Mail Account from cPanel but some of our customer still getting emails look like mails in queue, anyone know how to find queued mails and stop them? I need stop all outgoing emails from the queue...