Oppressed - The same word is used Exodus 3:9 of the oppression of Israel by the Egyptians. If they were put to task-work in hewing timber, their condition was very like that of their ancestors making bricks.
Related Commentaries of Judges 4:3
Judges 4:3
3 And the children of Israel cried unto the LORD: for he had nine hundred chariots of iron; and twenty years he mightily oppressed the children of Israel.