Feds allege Oahu man planned explosive, chemical attacks

A 20-year-old Honolulu man was indicted Wednesday by a federal grand jury on charges of possessing and attempting to possess a chemical weapon, and possessing an unregistered destructive device.

According to the indictment and other court documents, between approximately December 2019 and March, Ethan Sandomire conducted extensive research into explosives, explosive devices, chemical and biological weapons, and related topics, and wrote privately about his plans for explosive and chemical attacks in and around Honolulu, the according to the U.S. Department of Justice.


In early 2020, Sandomire allegedly ordered the materials to make a destructive device from multiple online vendors, which were then delivered to his residence. At or around the time of Sandomire’s arrest on March 29, the FBI said it seized the items that Sandomire had ordered online from a separate location, including, among other things: approximately 30 pounds of aluminum powder, approximately 30 pounds of ultra-pure potassium perchlorate, approximately 45 pounds of potassium perchlorate, and multiple ignition systems, wireless firing systems, and victim-initiated tripwire systems.

On Feb. 24, Sandomire allegedly had went to a hardware store in Honolulu and purchased items that, when combined, create chlorine gas, a toxic chemical. That same day, Sandomire searched the internet multiple times for the blueprints and floor plans of a large residential apartment building centrally located in Honolulu (“Building A”). Building A has approximately 450 residential apartment units, several commercial units, and a multi-level grocery store.

Two days later, on Feb. 26, the indictment charges Sandomire visited Building A in person. Security camera footage showed Sandomire waiting outside the main lobby for someone to exit, then walking into the lobby before the doors closed, and taking the elevator to the sixth-floor parking area. He took pictures on his cellphone of structural support columns inside the parking garage that is located below Building A’s outdoor recreational area and lap pool. He also took pictures of a storage area and large air vents coming out of an air handler that serves a 16,000-square-foot space elsewhere in Building A.

Sandomire returned to Building A’s main lobby and asked for copies of the building’s floor plans from the front desk staff, which the staff member did not provide, according to the Department of Justice. He also visited the building developer’s office and took photographs of a physical model of Building A.

Sandomire’s personal computer contained a desktop note entitled “destroy [Building A]” by using chemicals and explosives, among other thing, and numerous folders with extensive research into explosives, chemical weapons, biological weapons, improvised munitions, and similar topics. Some of the folders were entitled “building demolition,” “my attack plan,” “explosives,” and “bio warfare.” The folders contained digital versions of approximately 54 books about explosives and related topics. Sandomire’s computer also contained an instructional document titled “Advanced Chemical Weapons Design and Manufacture,” with the subtitle “Chemicals that Kill in 30 Seconds or your Money Back.”


The indictment filed Wednesday accuses Sandomire of one count of possession of a chemical weapon, which carries a maximum statutory penalty of life imprisonment and a fine of not more than $250,000, and one count of possession of an unregistered destructive device, which carries a maximum statutory penalty of 10 years’ imprisonment and a fine of not more than $10,000.

“My office will use the tools at its disposal to protect the community from those who possess destructive devices and chemical weapons. These kinds of cases underscore the importance of vigilant action by law enforcement to protect the public from the acquisition and use of materials that can cause devastating harm to our communities. This is the second case this year brought by my office that involves a violation of the federal chemical weapons statute, and we will continue to vigorously pursue, and bring to justice, those who endanger our communities by violating this law,” said U.S. Attorney for the District of Hawaii, Kenji M. Price.

Leave a Reply

Your email address will not be published. Required fields are marked *


By participating in online discussions you acknowledge that you have agreed to the Star-Advertiser's TERMS OF SERVICE. An insightful discussion of ideas and viewpoints is encouraged, but comments must be civil and in good taste, with no personal attacks. If your comments are inappropriate, you may be banned from posting. To report comments that you believe do not follow our guidelines, email hawaiiwarriorworld@staradvertiser.com.