In a cataclysmic event that has reverberated across Austria, a disaffected alumnus unleashed a fusillade of gunfire at a school in Graz, the nation's second-largest metropolis, resulting in the deaths of ten individuals and inflicting grievous bodily harm upon a further twelve, before perpetrating a final, self-inflicted act of fatal violence, according to official pronouncements.

The perpetrator, a 21-year-old male with no prior criminal history, employed two legally-owned weapons in the commission of the act, according to police sources, though his underlying motivation remains, as yet, entirely opaque.

"Speaking to reporters in Graz, the southeastern Austrian city of some 300,000 inhabitants, Austrian Chancellor Christian Stocker lamented what he termed a tenebrous day in the annals of the nation."

He characterised the event as "a profound national tragedy, the reverberations of which have shaken the collective conscience," announcing a three-day period of national mourning, during which the Austrian flag would be flown at half-mast on all official edifices, culminating in a nationwide minute of silence Wednesday morning to commemorate the deceased.

Following reports of gunfire at the BORG Dreierschützengasse Gymnasium, situated approximately one kilometre from Graz's Altstadt, at 10:00 hours, units of the Spezialkräfte were dispatched, resulting in the deployment of over 300 Polizei personnel to the site and the subsequent Räumung of the institution, with Aufnahmen from the location depicting Schülerinnen und Schüler zügig verlassing the premises under the watchful eyes of schwer bewaffneten Beamten.

In a remarkably swift seventeen-minute interval, law enforcement authorities comprehensively re-established the requisite security parameters.

Law enforcement officials have disclosed that the perpetrator, identified as a 21-year-old Austrian national residing in the vicinity of Graz, acted unilaterally; however, his identity remains protected under investigatory protocol.

Regionalpolizeidirektor Gerald Ortner konstatierte, dass bei der Schießerei zwei Schusswaffen zur Anwendung gelangten – ein Langgewehr sowie eine Handfeuerwaffe –, welche am Tatort sichergestellt wurden, und dass der Täter diese offenbar rechtmäßig besessen habe, ehe er sich in einem Sanitärraum das Leben nahm.

Interior Minister Gerhard Karner divulged that the assailant had been an alumnus of the institution, his matriculation having been incomplete, though he demurred from specifying the temporal juncture of his departure or his age at the point of cessation.

Karner stated Tuesday afternoon that the deceased comprised six women and three men, refraining from elaborating further; twelve individuals sustained injuries. Subsequently, the state hospital in Graz, via the Austria Press Agency, communicated the demise of a tenth casualty, a woman who succumbed to her injuries.

The Austrian Red Cross has galvanised its resources, dispatching 65 ambulances to the calamitous locale while 158 highly-trained emergency personnel administer critical care to the wounded; simultaneously, a cohort of 40 specialised psychologists are providing crucial psychosocial support to traumatised students and parents, and a public appeal has been launched imploring local citizens to contribute to blood reserves.

Metin Özden, ensconced in his kebab emporium proximate to the school, initially registered the precipitate passage of police vehicles, swiftly succeeded by the auditory intrusion of a constabulary helicopter; subsequently, he divulged to the Krone Zeitung, “I intuited the occurrence of some grave incident… Never in my quinquagenarian existence have I witnessed such a confluence of emergency personnel.” He further elucidated to the aforementioned periodical his observation of distraught parents, lacrimose and palpably grief-stricken, traversing the thoroughfare adjacent to his establishment en route to the educational institution.

Tuesday's paroxysm of violence seemingly constituted the most lethal assault on Austrian soil in the post-bellum era.

The sanguinary Vienna attack of 2020 resulted in four fatalities, with the perpetrator, an alleged Islamic State sympathizer, also perishing in the fusillade, and leaving over twenty individuals, including a member of law enforcement, with grievous bodily harm.

In June 2015, a malevolent actor perpetrated a vehicular massacre in Graz's city centre, resulting in three fatalities and leaving over thirty individuals grievously wounded after he deliberately ploughed an SUV through a throng of pedestrians.

Despite its deeply entrenched hunting heritage, Austria maintains comparatively permissive firearms legislation within the European Union's regulatory framework.

In Austria, the acquisition of certain manually-reloaded firearms, including rifles and shotguns, is permissible from the age of 18 without requiring a specific permit, contingent solely upon verification by licensed dealers of the absence of any extant weapons prohibition pertaining to the purchaser and subsequent mandatory registration of the firearm within the centralised national registry.

The acquisition of alternative armaments, encompassing repeating shotguns and semi-automatic firearms, presents a more arduous undertaking, predicated as it is upon the possession of both a gun ownership card and a firearms pass, thereby imposing a bureaucratic gauntlet.