Divers brought up a body from the wreck on Monday, and another body was pulled from the river 100 kilometers (60 miles) downstream.

The search has extended hundreds of kilometers south, into Serbia, as bodies have floated downstream. South Korea has asked Hungary to reinforce the search around Harta, where the body was found on Monday, Korean Embassy Defense Attache Song Shun-keun said.

The Danube’s flooding has hampered recovery work, officials said, but waters are receding now.

“The operational environment continues to improve,” Song told a news briefing. “But we are still struggling to get into the ship due to bad visibility.”

Korean Deputy Foreign Minister for consular affairs Lee Sang-jin, who is in Budapest to lead the emergency response team, said he expected soon to be able to start returning to South Korea the bodies already identified. If they’re willing, survivors may speak to Hungarian investigators later on Tuesday, Lee added.

South Korean and Hungarian rescue and recovery teams have set up bases on the river and on the nearby Margaret Island, within sight of the crash site. They might mobilize drones if visibility improves, the attache said.  

Song expects salvaging the vessel to begin Thursday, after a crane is delivered. Work may begin on Friday or Saturday, he added.

South Korea has asked Hungary to ensure that the captain of the cruiser, a 64-year-old Ukrainian under arrest pending bail, is not released. His lawyers said the captain was devastated by the accident but had done nothing wrong.