Hungarian police say the tour boat that sank in the Danube River late Wednesday, killing seven South Koreans and leaving 19 others missing, abruptly turned in front of a larger cruise ship before they collided.

During a press conference on Thursday, Police Colonel Adrian Pal revealed footage of the collision and said the sightseeing boat, the "Hableany," made a sudden turn before the Viking Sigyn cruise ship rear-ended it near the Margit Bridge at 9:05 p.m. local time.

The smaller boat sank within seconds of the impact.

Imre Horvath, the head of the Hungarian National Shipping Association, told a local media outlet on Thursday that he believes the accident was a result of human error.

Horvath said the Viking ship was likely equipped with a global positioning system to maintain at least a four-meter distance from other vessels. He stressed that the field of vision at the time of the accident was good enough to confirm the movement of other boats.