Police in Hungary say they detained a river cruise boat captain as part of their investigations into a fatal collision on the Danube River.
They say a small motor boat carrying eight people was struck late at night at the weekend.
Only one man has survived with two bodies recovered from the water and five still missing.
The captain of the river cruise ship Heidelberg, who is a Czech national, is suspected of various offences including failure to stop and provide assistance after the collision.
Police say he did not alert his crew or follow normal protocol after the collision.
No charges have been filed yet.
The collision only came to light after a 35-year-old man was discovered on land 30 miles from Budapest after swimming to the river bank with a head wound.
So far, hundreds of people have been searching along the river for the five missing people, according to László Balázs, head of Pest County Search and Rescue Service.
Police have interviewed and taken statements from multiple crew and passengers on the river cruise ship.
The vessel was carrying 110 people at the time.
