A dramatic and highly unusual emergency unfolded on Saturday, 20 December 2025, when a two-trailer truck laden with around 15 tonnes of lithium-ion batteries erupted in flames on the Hume Highway near Yass, New South Wales, forcing authorities to shut the vital interstate route in both directions and issue urgent public health warnings.
The incident — involving a type of cargo increasingly common on highways but notoriously difficult to contain once ignited — triggered chaos for motorists making their way through the state during the peak holiday travel season and raised fresh concerns about the growing fire risk posed by lithium-ion batteries.
Blaze Erupts on Busy Freight Route, Toxic Smoke Drives Response
Shortly after 9 a.m. local time on Saturday, emergency services were called to a fire aboard a B-Double truck transporting heavy lithium-ion batteries, each weighing roughly 300 kg and totalling some 15 t of cargo, when the blaze broke out while the vehicle was heading south. Fire and Rescue NSW crews, along with the NSW Rural Fire Service, raced to the scene on the Hume Highway near Yass — a key freight and travel artery linking Sydney and Melbourne.
Once firefighters arrived, the scale of the challenge quickly became clear. Lithium-ion battery fires burn at extremely high temperatures and can emit toxic gases and vapours, meaning they are not only difficult to extinguish but also pose serious health risks to responders and anyone close by. Authorities established a 700-metre exclusion zone and advised locals, especially those with respiratory illnesses, to stay indoors with windows and vents closed.
Traffic was halted in both directions, and with holiday traffic already heavy, the shutdown quickly led to kilometres of vehicles backed up as travellers sought alternate routes or waited for conditions to improve. Police advised against travel through the area and warned the closure could last several days given the complexity of containing the fire and the health risks involved.
Complexity of Lithium-Ion Fires Forces Unusual Tactics
Firefighters confirmed they detached the truck’s cabin and smaller trailer from the burning main unit before those sections could catch fire themselves. That isolated the blaze but did not extinguish it — because the batteries continued to undergo thermal runaway, a process in which cells overheat and trigger neighbouring cells in a chain reaction.
Given the hazard of contaminated water runoff entering drains and local waterways if large volumes of water were used, fire crews indicated they were likely to allow the fire to burn itself out rather than attempt full manual suppression, a strategy used increasingly in battery fires when conventional methods pose greater environmental risks.
Lithium-ion battery fires are challenging because they can reignite unexpectedly and release a cocktail of hazardous emissions, including hydrogen fluoride and other volatile compounds. In NSW, firefighters have identified these incidents as an emerging and serious hazard, with lithium-ion batteries described as the “fastest-growing fire risk” due to their prevalence in electric vehicles, e-bikes, e-scooters, and industrial applications.
Public Safety and Health Warnings
NSW Police and Fire and Rescue issued multiple alerts telling motorists not to approach the scene and urging residents of the Yass Valley area to be cautious. People were advised to shelter indoors and delay travel plans as authorities monitored air quality and managed the exclusion zone. Given the toxic nature of emissions from burning batteries, public health officials underscored that even brief exposure near the scene could be harmful, particularly for vulnerable groups such as the elderly and those with pre-existing respiratory conditions.
On social media and local community pages, police emphasised that the closure was not security-related or suspicious in nature, but rather a necessary public health and safety measure due to the dangerous nature of the cargo involved.
Travel Chaos and Community Response
The timing of the incident, coinciding with summer holidays and heavy interstate traffic, exacerbated its impact. Many travellers found themselves stuck in extended delays, with some families choosing to leave vehicles on the side of the road and seek relief from the heat and fumes. In Yass township, local residents and business owners stepped in to help, handing out water and ice blocks to stranded drivers as temperatures climbed and frustration grew.
By evening, a single northbound lane had reopened, but southbound traffic remained blocked, and authorities cautioned drivers to expect substantial delays and to plan alternative routes.
Broader Safety Concerns Around Lithium Batteries
This incident has also reignited debate about the regulation, transport and storage of large lithium-ion battery consignments. In recent years, NSW firefighters have reported a dramatic increase in battery-related fires — from household devices to larger commercial units — and have called for tighter safety standards and clearer guidelines on handling and transport to prevent similar events.
Lithium-ion technology, while ubiquitous in modern life, carries well-documented risks, particularly when cells are damaged, improperly stored, or exposed to heat. Fires can start from manufacturing defects, poor packing, or physical impact, and once ignited, they are notoriously difficult to bring under control.
What Comes Next
At the scene, emergency services must continue to monitor the area for flare-ups and assess environmental risks as the fire slowly diminishes. Traffic authorities are urging travellers to continue avoiding the corridor where possible, and diversions through local roads are expected to remain in place while the blaze burns through the remaining battery units.
The broader incident underscores the challenges facing emergency responders and transport regulators as the freight system adapts to carry new technologies that, while critical to the energy transition and modern electronics markets, present unique hazards that existing systems are still learning to manage.
As authorities work toward reopening the highway fully — and as investigations into what triggered the fire continue — the Hume Highway disruption serves as a stark reminder of the evolving complexities on modern roads and the trade-offs between innovation and safety.
7 years in the field, from local radio to digital newsrooms. Loves chasing the stories that matter to everyday Aussies – whether it’s climate, cost of living or the next big thing in tech.
