They are scattered on the ground where an enemy's cavalry are to pass, to impede their progress by endangering the horses' feet.
crime of endangering peace
[法] 危害安宁罪
crime of endangering public affairs
[法] 妨害公务罪
crime of endangering public security
[法] 危公共安全中罪
endangering
v. 危及, 使遭受危险( endanger的现在分词 )
