CHICAGO (CBS) — The parents of a Bolingbrook teenager accused of trying to join the Islamic State in Syria said the terrorist group is “brainwashing” youth through social media, and condemned ISIS for “unspeakable acts of horror”

Shortly after her son pleaded not guilty to terrorism charges, Zarine Khan tearfully denounced the Islamic State, and last week’s deadly terrorist attack on a Paris newspaper, which has been tied to both ISIS and al Qaeda.

“We condemn the brutal tactics of ISIS and groups like it, and we condemn the brainwashing and recruiting of children through the use of social media and Internet,” she said, her voice trembling with emotion.

With her husband and her son’s attorney at her side, Zarine Khan said she felt compelled to speak out against the “unspeakable acts of horror” committed in France last week.

“The venom spewed by these groups, and the violence committed by them find no support in the Koran, and are completely at odds with our Islamic faith. We condemn this violence in the strongest possible terms,” she said.

Two brothers killed 12 people at the Paris office of the satirical Charlie Hebdo magazine last week. Police have found a video of one of the gunmen expressing loyalty to ISIS, and al Qaeda has said it directed the attack in retaliation for the magazine publishing a cartoon of the Muslim prophet Muhammad. Images of Muhammad are forbidden in the Islam religion.

Last week, a federal grand jury formally indicted Khan’s son, 19-year-old Mohammed Hamzah Khan on a single count of attempting to provide material support to a foreign terrorist group.

The teen was arrested last October at O’Hare International Airport, while allegedly trying to fly to Austria, and then Turkey, in an effort to join ISIS militants in Syria. Federal prosecutors have said he and two younger siblings expressed a desire to commit violence, and act on “barbaric rhetoric” if they managed to sneak into Syria and join the Islamic State terrorist group, which has seized control of large swaths of Iraq and Syria.

The younger siblings have not been charged with a crime.

Zarine Khan said her son was brainwashed and fell under the influence of Islamic State propaganda, and she called out ISIS leader Abu Bakr al-Baghdadi.

“We have a message for ISIS, Mr. Baghdadi, and his fellow social media recruiters: leave our children alone!” she said.

Defense attorney Thomas Durkin said Mohammed Hamzah Khan was radicalized online before his arrest.

After Khan was detained at O’Hare, federal agents obtained a warrant to search his home, where they allegedly found hand-written documents there that appeared to be drafted by Khan and/or others, expressing support for the Islamic State.