(Adds prosecutor's ******, report, lawmaker) PARIS, **v 19 (Reuters) - France believes a Second French militant appears on a beheading video released by Islamic State at the weekend, government spokesman Stephane Le Foll said on Wednesday. Officials said on Monday that one of the men shown herding prisoners to their execution was Maxime Hauchard, a Frenchman Muslim convert who left for Syria in 2013. Further analysis suggested a**ther French citizen also took part in the video. "It seems that there is a Second Frenchman," Le Foll told BFM TV. ...