In a harrowing incident unfolding in Austria's second-largest metropolis, a disaffected alumnus unleashed a fusillade upon his former school on Tuesday, leaving ten individuals deceased and a dozen more grievously wounded, culminating in his own self-inflicted demise, according to official pronouncements.

The perpetrator, a 21-year-old male with no prior criminal history, employed a dual-weapon system in the commission of the act, the impetus for which remains, as yet, unelucidated; law enforcement authorities have indicated that the weapons in question were, ostensibly, legally acquired and possessed.

"In Graz, a southeastern Austrian conurbation of some 300,000 souls, Austrian Chancellor Christian Stocker lamented to assembled reporters that the present day represented a nadir in the annals of the nation."

He characterised the event as "a profound national tragedy, the reverberations of which shock the collective consciousness," decreeing a three-day period of national mourning, signified by the lowering of the Austrian flag to half-mast on all official edifices, to be punctuated by a national minute of silence held Wednesday morning in solemn commemoration of the deceased.

Following reports of gunfire at the BORG Dreierschützengasse gymnasium, situated approximately one kilometre from Graz's historic Stadtkern, at 10:00 hours, specialist tactical units were deployed, precipitating the mobilisation of over 300 Polizei personnel and the exfiltration of all students, as evidenced by visual documentation depicting their rapid egress under the aegis of heavily armed officers.

Law enforcement affirmed the reinstatement of security protocols within a circumscribed timeframe of seventeen minutes.

Law enforcement officials have confirmed that the perpetrator, a lone actor identified as a 21-year-old Austrian national residing in the vicinity of Graz, remains unnamed pending further investigation.

Regionalpolizeidirektor Gerald Ortner konstatierte, dass bei der Schießerei zwei Schusswaffen – ein Langgewehr und eine Handfeuerwaffe – zum Einsatz kamen, welche beide am Tatort sichergestellt wurden, wobei der Täter diese offenbar rechtmäßig besaß; anschließend habe sich der Mann in einem Badezimmer das Leben genommen.

Interior Minister Gerhard Karner divulged that the assailant had been an erstwhile student of the institution, his studies incomplete, though he remained reticent as to the specific temporality of the man's departure or his age at the time of cessation.

Karner stated on Tuesday afternoon that the deceased comprised six women and three men, withholding further particulars; he added that twelve individuals had sustained injuries. Subsequently, the state hospital in Graz, via the Austria Press Agency, announced the death of a tenth victim, an adult female, succumbing to her injuries.

The Austrian Red Cross, having dispatched a fleet of sixty-five ambulances to the cataclysmic locus, confirmed that a cohort of one hundred and fifty-eight paramedics are currently administering on-site triage; furthermore, a cadre of forty highly specialized psychologists are providing acute trauma counseling to both students and their families, whilst the organization simultaneously appeals to the populace for immediate blood donations to mitigate the exigent circumstances.

Özden, proprietor of a kebab emporium proximate to the scholastic institution, initially registered the heightened activity – the precipitate passage of constabulary vehicles, swiftly succeeded by the aerial presence of a police rotorcraft. He subsequently divulged to Krone reporters, "I intuited that some calamitous event had transpired… I have never before borne witness to such a confluence of emergency responders in my existence." Furthermore, he recounted to the aforementioned publication his observation of distraught parents, lacrimose and grief-stricken, traversing the thoroughfare adjacent to his establishment en route to the school.

Tuesday's conflagration seemingly constituted the most lethal episode in Austria's post-bellum history.

In Vienna, 2020, a fusillade perpetrated by a putative Islamic State sympathizer resulted in four fatalities, the assailant's demise, and left over twenty wounded, including a member of the law enforcement cadre.

In June 2015, a malevolent actor perpetrated a vehicular massacre in the heart of Graz, resulting in three fatalities and inflicting grievous bodily harm on over thirty individuals, as he weaponized an SUV to plow through a throng of unsuspecting pedestrians.

Despite its deeply ingrained hunting heritage, Austria maintains comparatively permissive firearms legislation within the European Union.

In Austria, the acquisition of certain manually-reloaded firearms, including rifles and shotguns, is permissible from the age of 18 without requiring explicit licensing, contingent upon a dealer's verification of the absence of any pertinent weapons prohibition concerning the purchaser, and subsequent mandatory registration of the weapon within the centralised national registry.

The acquisition of other ordnance, encompassing repeating shotguns and semi-automatic firearms, is subject to a more stringent regulatory framework, predicated on the possession of both a gun ownership card and a firearms pass.