Emergency services are attempting to rescue as many people as possible, but the water level is high.
Budapest: At least seven tourists from South Korea lost their lives and around 19 other people went missing after a sightseeing boat they were travelling in sank following its collision with another vessel on the Danube River here on Wednesday evening (local time), authorities said.
CNN confirmed after quoting a spokesman for the tour operator as saying that 34 people were on board, including the crew.
Hungarian authorities further said that officers from Budapest Police headquarters, as well as disaster management and rescue service personnel, are handling the rescue operation.
The Mermaid, a ship from Panorama Deck's tourist fleet operating on the Danube since 2003, sunk shortly before 10 p.m. Wednesday, Panorama Deck spokesman Mihaly Toth told CNN.
Emergency services are attempting to rescue as many people as possible, but the water level is high, and for that reason "the Danube is very strong," he said.
In addition, heavy rain is also impeding emergency responders' efforts to search the water's surface.
There were "no signs of a possible issue with the boat," the spokesman said.
Panorama Deck "ensures all the necessary technical maintenance is carried out every year" on their fleet, he added.
"We cannot confirm why the boat sank -- it was just an average day, and this was a regular trip. We carry out thousands of tourist boat trips every day, there were no signs that something like this could happen," he was quoted as saying.
Meanwhile, South Korean President Moon Jae-in called for every possible means, in cooperation with the local authorities of Hungary, to rescue the South Korean tourists.
The President's Office on Thursday said that the Seoul has plans to dispatch a team of officials to Hungary as well.
Providing further details on the report, the Office stated that the sightseeing ship was carrying 32 South Korean passengers and two crew members when it sank in the Danube River in downtown Budapest on Wednesday.