Do I need Police Clearance Certificate from Afghanistan for my I-130 petition?

I filed I-130 peition for my wife (who is in Afghanistan) which is approved and is pending in National visa center. Now we are required to submit additional documents with the immigrant visa application. Under required documents, it says that my wife must submit police clearance certificate. However, it also states that police clearance certificates are NOT available in some countries. Is my wife, who is citizen and resident of Afghanistan, required to obtain the police certificate from Afghanistan? Thanks