CHICAGO (WLS) -- There are more serious charges against a Maine teenager who's accused of plotting an ISIS-inspired attack on a mosque in Chicago.
Xavier Pelkey, 19, is now charged with conspiracy to provide material support to terrorists, along with the possession of unregistered destructive devices.
According to an FBI search warrant obtained by the I-Team, Pelkey planned to separate worshipers at a Chicago Shia mosque then kill all the adults.
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Investigators cited statements from other teenagers allegedly involved in the plot, evidence that Pelkey planned to bring guns and ammunition to Chicago in addition to the explosive devices.
The homemade bombs, according to court records, were cooked up and concocted out of easily purchased items. That is the new ISIS MO: use what you have and can find to maim and kill.
According to federal law enforcement, Pelkey's home in rural Maine was bomb central.
Months ago the teenager allegedly had an intricate ISIS-inspired plot with associates in Kentucky and Illinois and targets included churches, mosques and synagogues in Chicago.
Initially, in Maine federal court, Pelkey was charged with simple crimes: possession of explosive devices.
But this month he was indicted on terrorism related charges. Wednesday, he went before a federal judge and pleaded not guilty.
The superseding indictment from a few weeks ago may indicate that this was a more serious threat to Chicago than first thought.
"It does in the sense that the superseding indictment now brings a charge of terrorism of providing material support, conspiring to provide material support to terrorists by definition, that's a more serious charge and posed a greater threat to the people in Chicago, then the original charge," said ABC7 legal analyst Gil Soffer, "The defendant who is being charged with lending material support to terrorists that carries a 15 year maximum sentence. It doesn't mean that's what he's going to get. But it means he'll get some real jail time."
Soffer, who is also a former assistant U.S. attorney in Chicago, warned teenagers about the seriousness of terror-inspired conversations online.
"Guys, I don't think there's any question the message is, you may be watched, you may be talking to an undercover informant, you may be discovered in some other fashion....the presence of these weapons certainly support the government's theory here, that you could face real consequences just as this defendant is facing," said Soffer.
The Chicago terror attack never happened. FBI agents claim they intercepted the accused attackers before any onslaught.
Pelkey is the only one charged in this case even though juvenile accomplices in Chicago and Kentucky were involved in the plot, according to federal agents.
It isn't known whether those teenagers were government plants or whether they cut early deals to cooperate and will be witnesses.