Both man and beast; for as the beasts were made for man's use and service, so they are destroyed for man's punishment, and to discover the malignity of sin, and God's deep abhorrency thereof, by destroying those innocent creatures that had been made instrumental to it.
Related Commentaries of Genesis 6:7
Genesis 6:7
7 And the LORD said, I will destroy man whom I have created from the face of the earth; both man, and beast, and the creeping thing, and the fowls of the air; for it repenteth me that I have made them.