Dangerous signs. Should a sign be or become insecure or in danger of falling or otherwise unsafe in the opinion of the Building Inspector, the owner thereof or person maintaining the same shall, upon receipt of written notice from the Building Inspector and in any case within five days thereafter, secure the same in a manner to be approved by the Building Inspector. If such order is not complied with, the Building Inspector is hereby authorized to cause removal of such dangerous sign, and any expense incident thereto shall be paid by the owner of the building, structure or premises on which such sign is located. The cost of removal shall constitute a lien on the real property on which it is levied until paid or otherwise cancelled pursuant to law and shall be collected in the manner fixed by law for the collection of Town taxes. When any sign is in such dangerous condition as to be immediately dangerous to the safety of the public, the Building Inspector is hereby authorized to take such action as in his opinion shall be necessary to protect the public or property.