In the aftermath of the disaster, representatives from both the Republic and Confederacy were sent to Cato Neimoidia to investigate. The Separatist emissary, Dark Acolyte Asajj Ventress, sought to stoke Neimoidian discontent with the Republic. The Republic representative, Jedi Master Obi-Wan Kenobi, met a Neimoidian Royal Guardswoman, Ruug Quarnom, who began working on the investigation with Kenobi. The Jedi and his companion discovered both Republic and Separatist weaponry had been used to carry out the bombing, leading them to conclude that the attack had been carried out by a third party who was playing both sides of the conflict.
In 22 BBY, a political schism within the Galactic Republic regarding the breakaway Confederacy of Independent Systems came to a head when open warfare broke out between the two factions. The conflict, the first galaxy-wide war in a millennium, became known as the Clone Wars. One prominent member of the Separatist movement was Nute Gunray, the Viceroy of the Trade Federation, a Neimoidian megacorporation. Despite Gunray's membership in the Executive Separatist Council, the Federation officially remained neutral in the conflict, stating that Gunray led an extremist, breakaway faction who did not represent the views of the corporation as a whole. Their neutrality extended to the planet Cato Neimoidia, the location of the Federation's headquarters.
The Clone Wars had been secretly masterminded by the Sith, an ancient order which wielded the dark side of the Force, as part of a plan to rule the galaxy. The two Sith Lords who masterminded the conflict, Darth Sidious and Darth Tyranus, were publicly Supreme Chancellor Sheev Palpatine of the Republic and Head of State Count Dooku of the Confederacy. The two regularly arranged events to ensure the war continued to escalate, stymieing any efforts to ensure a peaceful resolution. To that end, the Sith's attention turned to Cato Neimoidia to further set the Republic and Separatists at odds.
The Neimoidian species had a troubled relationship with the Galactic Republic. Their psychological makeup made Neimoidians inherent calculators of risk, which contributed to a stereotype amongst the Republic that they were all greedy, amoral merchants and bankers. Although the Trade Federation was highly respected in Neimoidian society because it was their predominant voice on the galactic stage, Nute Gunray and his ilk encapsulated every negative Neimoidian stereotype in existence.
The Cadesura district, a cultured area of Cato Neimoidia's capital city of Zarra, was targeted for an attack. Bombs were placed throughout the area, with munitions from both of the Clone Wars' warring factions used, including personal-scale versions of Separatist blazer bombs. Viceroy Gunray paid a visit to Cadesura only an hour before the bombing.
When the bombs were detonated, the Cadesura district was severed from the bridge city's superstructure and sent plummeting to Cato Neimoidia's surface. Over three thousand civilians were in Cadesura at the time, resulting in a death count of around three thousand two hundred. Units of the Neimoidian Royal Guard were dispatched immediately, including Ruug Quarnom, a former commando in the Neimoidian Defense Legion, and her more inexperienced colleague Ketar Nor. Medical personnel and passing civilians also raced to the scene to offer assistance.
Republic government personnel on Coruscant heard about the attack almost as soon as it happened. The news prevented Chancellor Palpatine from attending a ceremony marking the promotion of several new Jedi Knights at the Jedi Temple in person. Count Dooku claimed Separatist innocence in the attack and challenged the Republic to send Palpatine to Cato Neimoidia in person to prove they were not responsible. A deal was struck wherein Jedi Master Obi-Wan Kenobi travelled to Cato Neimoidia alone to investigate, denied contact with the Republic or the Jedi High Council for the duration.
During his investigation, Kenobi met Quarnom, but found himself up against Dark Acolyte Asajj Ventress, Dooku's apprentice, who radicalized Nor and framed Kenobi for crimes connected to the bombing. Together, Kenobi and Quarnom discovered from their gathered evidence the nature of the weapons used in the attack and concluded that a third party was attempting to play both sides of the conflict. Kenobi's former Padawan, Anakin Skywalker, discovered he was in danger and disobeyed orders to come to his rescue, with the two escaping Cato Neimoidia to bring their evidence back to the Republic. Quarnom was arrested for treason after being implicated by Nor, after which the Sith attempted to covertly dispose of her. However, the two Jedi discovered she was in danger and rescued her from battle droids sent to eliminate her.