The captain of a boat involved in a deadly river collision in Hungary was taken into custody on Thursday as hopes faded for any further survivors.

A small sightseeing boat collided with a larger river cruise ship on the Danube in Budapest on Wednesday, capsizing the smaller vessel.

It took just seconds for the Mermaid to sink with 35 people on board. At least seven people were confirmed dead on Thursday and 21 others were missing, while seven survived. Most of those on board were South Korean tourists on a group tour.

The Hungarian captain and a crew-member of the Mermaid are still missing.

At the time of the collision, most of the passengers were inside, sheltering from heavy rain.

Suspect questioned

Police arrested the 64-year-old Ukrainian captain of the 135-meter, four-story Viking Sigyn. He was "questioned as a suspect... in relation to endangering waterborne traffic resulting in multiple deaths."

Police said security camera footage "shows that before the collision, the Mermaid turned towards the German-built Viking Sigyn cruise boat for some reason. The Viking then turned the small boat over, and it sank within seven seconds."

"The current was so fast and people were floating away but the rescue team did not come," a rescued 31-year-old woman told South Korea's Yonhap news agency.

Ginger Brinton, an American tourist on board the Sigyn, said: "We were on our balcony, and we saw people in the water, screaming for help."

"We never felt any bump. We didn't realize. We just saw people in the water. It was just terrible."

Police said the 70-year-old Mermaid was serviced regularly and had no obvious faults.

The wreck has been located on the riverbed near the Margit Bridge and a floating crane set up to retrieve it. However, strong currents have frustrated recovery efforts.

The South Korean prime minister spoke to his counterpart on the matter, and has dispatched a crisis management team to the European Union member state.

aw/rc (AFP, AP, Reuters)

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