The head of the Osijek flood defence centre, Ivica Nadj, told Hina the measures were introduced when the river reached 652 cm, reiterating that a flood wave was expected on Friday.
The Defence Ministry said another 100 soldiers would be sent to Vukovar today to help with flood protection at the order of Minister Ante Kotromanovic and at the request of the Protection and Rescue Department.
One hundred soldiers are already helping in Nemetin near Osijek.