In the early hours of Tuesday morning, Greenwich University's Avery Hill campus transformed from a serene academic environment into a zone of unrest as four individuals fell victim to an enigmatic attack involving a mysterious liquid.

Responding swiftly to a distress call shortly after midnight, the Metropolitan Police and London Ambulance Service arrived to tend to a man with head injuries, victim of an apparent assault involving an unidentified substance.

As law enforcement scoured the locality, three additional individuals were discovered to have been sprayed with the non-toxic agent, intensifying the urgent inquiry into the motivations and identity of the assailant, who remains at large.

Though the substance was determined to be non-toxic, the unsettling nature of the attack has magnified concerns about public safety on campus.

'We are actively assisting police with their investigation,' a spokesman for the University of Greenwich stated, affirming that none of the injured were enrolled students.

The authorities have since removed the temporary closure of the campus entrance, yet tensions linger as the university community seeks reassurance amidst the crisis.

The intensity of the police investigation underscores the determination to bring the perpetrator to justice.

'At this early juncture, no arrests have been made, and urgent enquiries continue,' clarified a Metropolitan Police spokesman, reinforcing the necessity for vigilance as officers maintain a secured crime scene.

While the motive for this puzzling attack remains elusive, the incident has cast a shadow over the safety perceptions of academic spaces, traditionally seen as bastions of security and scholarship.

As the probe advances, the broader implications of campus safety and crisis preparedness gain salient relevance, calling for a deeper exploration of protective measures in education hubs worldwide.