On Friday, the FBI said that an 18-year-old boy from Maine and two underage minors planned to attack a Shia mosque in Chicago at the end of March.

Xavier Pelkey and two other unidentified 17- and 15-year-olds from the Chicago and Kentucky area used Instagram and other messaging programs to plan an attack on a mosque in late March during the “spring break.”

A charge of possessing an unregistered dangerous device was filed against Pelkey after he was apprehended on February 11.

Pelkey told one of his co-conspirators that he had developed an explosive device to “get more people” as part of the plan.

Before the assault, Pelkey and the other youngster from outside Chicago planned to take a train or bus into the city to meet their other coconspirator.

According to the court documents, one of the teens “explained that they would enter the Shia mosque and separate the adults from the children, then murder the adults. If they had not encountered law enforcement at that point, they would continue on to another Shia mosque or Jewish synagogue and execute the same plan. They did not have a plan to escape but rather their plan ended with them being shot by law enforcement.”

A multitude of weapons of mass destruction were discovered at the house of the 15-year-old boy in Chicago after an FBI search order was served on the property, the agency claimed. The FBI also found many handmade ISIS flags and numerous technological gadgets.

While speaking to the FBI, Pelkey “had talked about gathering materials to make fireworks to attack someone,” adding that he “told him that he wanted Allah to grant him to be a shaheed and die while fighting in the cause of Allah.”

Once the FBI gained access to the “Abdullah. ibn.Ahmad” Instagram account, Pelkey reportedly revealed to the FBI that he owned it and had used it to communicate with his collaborators.

Investigators reportedly discovered three handmade explosive devices and two ISIS flags that were hand painted in Pelkey’s bedroom during a search in February.