An Irondale man has been sentenced to federal prison for detonating an explosive device outside the Alabama Attorney General’s Office.

Kyle Benjamin Douglas Calvert, 27, pleaded guilty in August to malicious use of an explosive device.

A federal judge on Thursday sentenced him to nine years in prison.

“Kyle Calvert attacked the Alabama Attorney General’s Office with a shrapnel-filled explosive and then fled the scene, but this sentence ensures he will not escape accountability for his crime,” said U.S. Attorney General Merrick B. Garland. “Acts of violence like this one against our public institutions endanger public servants and entire communities, and they must not be tolerated.”

According to the plea agreement and other court documents, Calvert in the predawn hours of Feb. 24 detonated an explosive device outside of the AG Steve Marshall’s office in downtown Montgomery.

No one was injured.

Calvert admitted during his plea hearing to manufacturing the device. He used, nails and screws as shrapnel and accelerants to cause an explosion.

Prior to planting the device, Calvert placed stickers on various downtown buildings.

The stickers had graphics advocating for various political ideologies. Some stickers included the phrase “Support your local antifa.”

Among those stickers identified as being placed in Montgomery – and matching Calvert’s collection – included:

• An Antifa logo superimposed over a rainbow flag background, with the words, “ANTI-FASCISM IS COMMUNITY SELF-DEFENSE.”

• An image of a multi-tiered pyramid-like structure with individuals located on each tier, with the words, “TOPPLE ALL HIERARCHIES.”

• The “A” symbol, assessed to represent anarchy, next to an image of an AK-47 rifle, superimposed over a black background with leaves and flowers, with the words, “DEFEND NATURE.”

• A purple-colored sticker with a masked face inside of a female pictogram. The words at the top of the sticker read, “FEMINIST ACTION.”

• A white sticker with spatter font which reads, “EAT THE RICH.” The “A” inside the word “EAT” is in the shape of the anarchy symbol.

• An image of multiple masked and hooded individuals, one carrying a sling, and another wearing goggles. In the center of the sticker, the Antifa symbol is displayed above the words, “SUPPORT YOUR LOCAL ANTIFA.”

• A black sticker with red and white font with the words, “FRIENDS DON’T LET FRIENDS BECOME COPS.” A red anarchy symbol surrounded by a red heart are in the lower right corner of the sticker.

Calvert claimed in his plea that he has no affiliation with antifa.

Antifa, short for Anti-Fascist, does not describe a particular group, but rather describes individuals who adhere to what they consider as “anti-fascist beliefs.”

The term Antifa is often associated with anarchist violent extremists, individuals who, in addition to holding anti-fascist beliefs, are also opposed to capitalism and the current form of the U.S. government and who advocate violence to achieve their goals, the charging documents explained.

Surveillance footage showed that at 2:50 a.m. that morning, a person wearing a dark jacket, hat, mask and goggles, was seen on video in the area of the Alabama Statehouse.

At 3:03 a.m., the person was observed placing a sticker on the doors of the Alabama State Capitol building.

Then, at 3:35 a.m., the person was seen walking northbound in the area of Washington Avenue and Decatur Street towards the Attorney General’s Office.

At 3:42 a.m., surveillance footage captured a large explosion near the Attorney General’s Office.

At 3:43 a.m., the person was seen walking north on Bainbridge Street towards Monroe Street and away from the Alabama Attorney General’s Office.

Several minutes later, at about 3:49 a.m., a security officer working at the Southern Poverty Law Center (SPLC) called 911 to report that an explosion had occurred about five minutes prior, at the northwest corner of Washington Avenue and Bainbridge Street.

At 3:54 a.m., a Montgomery police officer arrived in the area. Because of the location of the explosion, the officer was unable to see any evidence of it from his vantage point.

At 4:13 a.m., records state, the officer cleared the call as unfounded.

The damage wasn’t then discovered until Monday morning when workers arrived back to the downtown area to begin the work week.

According to multiple video surveillance captures of the suspect and a thorough analysis of the video images, the subject appeared to be a white male, wearing a black or dark leather-like jacket, with dark colored pants, a gray or tan beanie hat, black or dark leather-like shoes, a blue facemask and goggles with a thick black strap with thick circular lenses.

Investigators used video surveillance footage of the suspect at known locations to estimate that he was about 6-feet, 2-inches tall and slender. He had a unique walk in which his toes pointed inward when he took a step.

The suspect’s walk appeared to be more pronounced on his right side which caused the appearance of a limp when he walked.

Investigators learned that the device was a coffee container-like which contained insulation material soaked in a gasoline or lighter fluid substance, a mortar, firecrackers and nails.

The FBI laboratory report classified the explosive as an Improvised Explosive Device (IED).

The general components of an IED consist of an explosive main charge, a fusing system, and sometimes a container and/or fragmentation.

Additional enhancements may be added to an IED to increase its destructive capability and lethality.

“This IED used commercially available pyrotechnic fireworks as the main explosive charge, a coffee can as a concealment container, and was enhanced with added fragmentation and ignitable liquids,’’ the FBI agent wrote. “The addition of metal screws, nails, and other hardware to this IED demonstrates weaponization characteristics due to the enhanced fragmentation effect that those materials would create. The addition of ignitable liquids to the IED demonstrates weaponization characteristics due to the enhanced ability for the IED to initiate a fire.”

“The action of placing and initiating the IED on the walkway beside a government building demonstrates that this device was used as a weapon against property and/or to cause injury/death,’’ the agent wrote.

The FBI investigated the case with assistance from ATF and AlEA.

Middle District of Alabama Assistant U.S. Attorneys Russell T. Duraski and Brett J. Talley prosecuted.