 Despite a 40-day siege, however, they failed to capture it.In 728 he led the southern expedition into Asia Minor, while his brother Sa'id ibn Hisham led the northern; neither appears to have been particularly successful.Muslim sources attribute to him the capture of the fortress of Charsianon in September/October 730, but Byzantine sources state that this was done by Mu'awiya's uncle, Maslama ibn Abd al-Malik.