What is the ruling regarding possessing weapons for the application of the highway robbery penalty?

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The perpetrators must possess arms. If they do not have arms, they are not considered muharibin because they cannot prevent those who pursue them. This point is not disputed. If they threaten using sticks and stones, they are considered muharibin, a view held by Al-Shafi'i and Abu Thawr, as these items function as weapons against life and limb, akin to iron.