Two workers were killed late last year in the construction work on the Strazevica tunnel on the Belgrade bypass road in Serbia.
The ground collapsed during shutter removal from the walls near a portal of the second 745m long bore where the men were working.
The Serbian road authority, JP Putevi Srbije, said investigations were ongoing and no comment on the cause of the collapse and fatalities was made.
The twin tube tunnels are being excavated in soft ground in the Resnik neighbourhood of Rakovica municipality. The contract to complete the partly built tunnel was awarded in late 2004 to Energoprojekt.
The Belgrade bypass involves construction of a total of 69km of road to the west and south of the city. The Strazevica tunnel is in a section of existing ring road being rehabilitated, and the works on that bypass section also involve stabilisation of landslides.
