On 9 June 2018 four people in Prague, Czech Republic, were surprised by a strong sudden storm while searching for a cache in 4 km long tunnel. They were carried by the tidal wave for almost the whole length of the tunnel to the Vltava river where the tunnel ends. One woman was found dead in the river a few hours later. Six days later a second body, that of a man in the group, was found in the river. Two exhausted drowning people were rescued from the river suffering mostly from numerous bruises and blunt traumas.