The tunnel has been closed to everyone except firefighters.
Rescue spokeswoman Magni Brandsoey said the truck driver was able to get out and call a rescue center. It was not clear how the trailer got loose.
Photos posted on Norwegian media show a huge black billow of smoke in the mountainous area in western Norway.
The explosion happened around 11 am (0900 GMT) in a 1,901 meter (6,237 feet) subsea tunnel linking two islands in the Sogn og Fjordane county.
You’ve reached your limit of {{free_limit}} free articles this month.
Subscribe now for unlimited access.
Already subscribed? Log in
Subscribe to read the full story →Subscribe to Business Standard digital and get complimentary access to The New York Times
Smart Quarterly
₹900
3 Months
₹300/Month
70% off
Smart Essential
₹810
1 Year
₹67/Month
70% off
Super Saver
₹1,170
2 Years
₹48/Month
Subscribe
Renews automatically, cancel anytime
Here’s what’s included in our digital subscription plans
Access to Exclusive Premium Stories
Over 30 subscriber-only stories daily, handpicked by our editors
Complimentary Access to The New York Times
News, Games, Cooking, Audio, Wirecutter & The Athletic
Business Standard Epaper
Digital replica of our daily newspaper — with options to read, save, and share
Curated Newsletters
Insights on markets, finance, politics, tech, and more delivered to your inbox
Market Analysis & Investment Insights
In-depth market analysis & insights with access to The Smart Investor
Archives
Repository of articles and publications dating back to 1997
Ad-free Reading
Uninterrupted reading experience with no advertisements
Seamless Access Across All Devices
Access Business Standard across devices — mobile, tablet, or PC, via web or app
70% off