He seeks public 's help in killing Arabic - speaking militant . A CIA source told CNN last month that more than 15,000 foreign fighters , including 2,000 Westerners , had gone to the civil war in Syria . The foreign fighter , possibly an American , appears to personally execute Syrians in a video . The second video released by ISIS shows the jihadist leading a mass execution . In the video , jihadist speaks first in Arabic , then in English .
He seeks public 's help in killing Arabic - speaking militant . The foreign fighter , possibly an American , appears to personally execute Syrians in a video . The second video released by ISIS shows the jihadist leading a mass execution . In the video , jihadist speaks first in Arabic , then in English .