Still, I am interested in understanding as many have said Martens is a source for considerations of legal behavior during the period.
Again to understand, it is stated that "Beja rebeled against the French."
I see in Martens (1802 English translation) on pages 289-290 and 292, the following:
Section 4
"From the moment we are at war, all those wha belong to the hostile state become our enemies, and we have a right to act against them as such; but our right to wound and kill being founded on self-defence, or on the resistance opposed to us, we can, with justice wound or take the life of none except those who take an active part in the war. So that, children, old men, women, and in general all those who cannot carry arms, or who ought not to do it, are safe under unless they have exercised violence against the enemy."
Section 6
"Those who, unauthorized by their profession or the order of their sovereign, exercise violences against an enemy, and fall into that enemy's hands, have no right to expect the treatment due to prisoners of war: the enemy is justifiable in putting them to death as banditti."
The act of rebeling means the village of Beja "exercised violence" against the French.
I leave aside modern views of "undue force" and other concepts of our age.
In the age of 1811 and despite however horrible, unpleasant or unwise the action of the French, a read of Martens suggests the French reaction could be justified.
Let me hasten to add, Martens has many comments that suggest certain acts are too barbarious (footnote on 293) or too cruel (page 292). Yet, he does not say they are against the "law of nations" (the title of his book).
As such, I agree with the acts as being "terror" yet - seemingly - "in bounds".
I must spend some time getting my head around this. - R