Updated

By Greta Van Susteren

Let's all go "Off the Record." This is a test for all Muslims in the United States, especially those who lead mosques and call themselves moderates.

ISIS says it will execute American Peter Kassig. He is next on their execution list. He is an aide worker from Indiana. He's innocent. He himself is a Muslim, having converted to Islam, but he is also an American. ISIS kidnapped him in Syria and now ISIS plans to behead him, citing the Koran as justification.

So here's my message to American Muslim leaders. You must condemn the ISIS interpretation of the Koran and demand the release of this innocent captive, loudly and now. This is an important test, an important test about you and about the content of the Koran and your interpretation of it.

We need to hear where Muslim leaders stand, and we need keep hearing it until ISIS has been wiped from the earth. Right now, an innocent American Muslim's life is on the line, and time is running out. Silence is not an option.

And that is my "Off the Record" comment tonight.