Slovenia's Civil Aviation Agency has announced a temporary ban on all commercial hot-air balloon flights after an accident last week in which four people died and 28 were injured.
"The CAA bans all commercial balloon flights until further notice," the agency said on its website, without specifying how long the ban would be in force.
A commercial balloon with 32 people on board, mostly tourists, crashed and burst into fire last Thursday near Ljubljana when a sudden change in the weather forced the pilot to attempt an emergency landing.
The Slovenian authorities said a couple with their 11-year-old child, and a woman, all of them Slovenian citizens, were killed in the tragedy.
Due to its size and the strong winds blowing close to the surface, the pilot lost control of the balloon, which hit a tree and caught fire, according to eye witnesses.
Media reports on Monday said the flight ban would remain in place while authorities checked the licences of commercial operators.
Local media had reported last week that the pilot did not have a valid flying license and had taken off despite warnings of possible storms. Police have not confirmed the reports.
Out of the 28 persons who were hospitalised on Thursday, two remain in critical condition, hospital authorities said on Monday.
Almost half of some 50 hot-air balloons registered in Slovenia fly on a commercial basis, an official of the Aeronautical Association of Slovenia told Slovenia's news agency STA.