A massive explosion in the early hours of Monday morning local time took place at a chemical factory in Samut Prakan, close to the Thai capital Bangkok.
A 19-year-old volunteer firefighter is a confirmed fatality following the incident, with dozens more injuries and vast damage to nearby homes.
There has been a evacuation of the surrounding area, as fears have grown throughout the day about the toxic fumes coming from the site.
Thick, black smoke has been billowing from the factory since the 3am explosion, and firefighting efforts have been hampered by a shift in wind direction later in the day.
It has moved in the evening towards a north-easterly direction, resulting in people living in the Lat Krabang and On Nut areas being told to stay indoors by authorities.
Make-shift evacuation centres have been made available at local schools and a government office for people who have been displaced from their homes.
The noise of the blast was so vast that people up to 5 miles from the site reported hearing it, and CCTV footage from nearby houses shows bright flashes and boom noises, followed by the resulting damage to several properties.
The Ming Dih chemical factory had its main blaze extinguished by mid-morning, but there is a styrene monomer tank which continues to burn some 18 hours after the original incident. Authorities have said that many tonnes of the chemical were in storage at the factory.
Helicopters were unsuccessful in their efforts to distinguish the fire using fire retardant, after navigating the hazards of dense smoke in a risky operation.
The Office of the Prime Minister, Gen Prayut Chan-o-cha, had ordered for rain clouds to be seeded so that a downpour might assist to absorb pollutants from the sky, however, later backtracked on this order citing concerns that toxic chemicals may be released into Bangkok’s canals and the Chao Phraya river.
62 people were injured it was confirmed, 12 of whom were firefighters.
The deceased volunteer firefighter was names as Korasit Raopan.
Most well known to produce disposable foam plates and cups, styrene monomer is a toxic liquid chemical that can release poisonous fumes if ignited.
Local disaster prevention official Chailit Suwannakitpong said authorities were attempting to evacuate all people out of the area, including doctors and patients from Samut Prakan’s main hospital where many casualties were being treated, over concerns regarding the fumes and chances of further explosions.
Officials gave the order to evacuate an area 5 kilometers (3 miles) around the scene.
Authorities are monitoring the air in the area around the fire, and Pollution Control Department official Thalerngsak Petchsuwan urged anyone remaining in the are to keep their doors and windows closed to limit the chances of inhaling any fumes.
“Those who breathe it in can get dizzy and vomit and it might cause cancer in the long term,” he said.
The initial explosion shook the terminal buildings at Bangkok’s main airport Suvarnabhumi, which is not too far from the site. Alarms were set off throughout the airport.
Airport officials said no flights had been canceled but they would monitor the situation as the day progressed and were prepared to “put in place contingency plans in case of emergency.”