An alternative to qmHandle is qmail-remove. One I like a bit better to be honest.

IMORTANT: Qmail must be stopped before doing anything with the qmail queue.

cd /usr/ports/mail/qmail-remove && make install clean

Create the “yanked” for deleted mails.

mkdir /var/qmail/queue/yanked

Example:

Delete all mails originating from a specific domain.

qmail-remove -r -p "@somedomain.com"