No Further Event Killers

Mark Daniel Gooch murdered 27-year-old Mennonite teacher Sasha Krause in January 2020 after travelling from Arizona to the Mennonite community where she lived near Farmington, New Mexico. Krause disappeared on January 18 while retrieving materials for a Sunday school class, and her body was discovered more than a month later in the Coconino National Forest near Flagstaff, Arizona. She had been shot in the head and her wrists were bound. Gooch, who had been raised in the Mennonite faith but later rejected it, was convicted of first-degree murder and kidnapping in October 2021 and sentenced to natural life imprisonment plus five years for kidnapping in January 2022.

Mark Douglas Hacking murdered his pregnant wife, Lori Hacking, in July 2004 after she uncovered years of deception about his education, employment and plans to attend medical school. After initially reporting Lori missing and participating in public searches, Hacking became the focus of the investigation as detectives uncovered evidence contradicting his account. He eventually admitted killing Lori, disposing of her body in a landfill and attempting to conceal the crime. In 2005, Hacking pleaded guilty to first-degree murder and was sentenced to life imprisonment with the possibility of parole.

Mark Sievers became infamous after orchestrating the brutal murder-for-hire killing of his wife inside their Florida home in 2015. The case shocked the United States because the victim was a highly respected physician and mother, while investigators later uncovered a conspiracy involving Sievers, close friends and hired killers. Authorities described the crime as a calculated and financially motivated murder plot driven by greed, personal dysfunction and manipulation. The investigation later exposed disturbing details involving staged alibis, conspiracy planning and violent execution-style attacks, transforming the case into one of Florida’s most heavily publicized murder-for-hire prosecutions.

Mark Howard Wilson Jr. was convicted of murdering brothers Robert Baker, 12, and Tayten Baker, 14, in Melrose, Florida, on August 26, 2020. Wilson was the boyfriend of the boys' aunt, Cynthia Guinan, and had moved with her and their young daughter into a shed on the Baker family's property only five days before the killings. Robert and Tayten were found beaten with a hammer and had their throats cut. Wilson was convicted of two counts of first-degree murder, burglary with assault or battery and armed burglary. A jury unanimously recommended death, and in January 2023 a judge sentenced him to death for both murders. The Florida Supreme Court affirmed his convictions and sentences in May 2025.

Marshella Chidester is an American woman convicted in connection with a fatal vehicle incident in Michigan in 2024. The event occurred when she drove into a building during a private gathering, resulting in multiple deaths and injuries. The case gained national attention due to the circumstances of the incident and the loss of young lives. Chidester was later convicted and sentenced to a lengthy prison term.

Martin Bryant became Australia’s most notorious mass murderer after carrying out the Port Arthur massacre in Tasmania on April 28, 1996. Armed with semi-automatic rifles, Bryant killed 35 people and injured 23 others across multiple locations around the historic Port Arthur tourist site, making it the deadliest mass shooting in modern Australian history. The massacre shocked Australia and triggered sweeping national gun law reforms under Prime Minister John Howard. Bryant’s name became permanently associated with mass casualty violence, firearm legislation, and public trauma across the country. The scale of the killings, the randomness of the victims, and the horrifying duration of the attack turned the Port Arthur massacre into one of the most historically significant crimes in Australian history.

Michael Swango became one of the most notorious medical serial killers in American history after being linked to a series of poisonings involving patients, coworkers, and acquaintances over several decades. A licensed physician and former paramedic, Swango exploited positions within hospitals and medical institutions to gain access to vulnerable victims while maintaining the outward image of a highly educated healthcare professional. The case generated international attention because Swango continued obtaining medical employment despite repeated suspicions, disciplinary actions, and criminal convictions. Investigators later connected him to deaths and poisonings across the United States and Africa, leading many experts to believe the true number of victims may never be fully known. His ability to repeatedly evade detection turned the case into one of the most disturbing examples of institutional failure and medical predation in modern criminal history.

Mikhail Viktorovich Popkov, known as the "Angarsk Maniac" and "Werewolf," is a former Russian police officer who murdered women across the Irkutsk region between 1992 and 2010. He typically approached women at night in his police vehicle, offering them rides before taking them to isolated locations where he sexually assaulted and murdered them using weapons including knives, axes, screwdrivers and ropes. Popkov was arrested in 2012 after DNA testing connected him to the killings and was subsequently convicted in multiple trials. By 2026, courts had established his responsibility for 91 murders and three attempted murders, making him one of Russia's most prolific serial killers. He is serving life imprisonment in a special-regime prison in Mordovia.