Scientist trapped 500 metres underground in Croatia
Rescuers in Croatia are trying to reach a scientist trapped at a depth of some 500 metres in the country's largest cave system.
The Croatian Mountain Rescue Service (GSS) said on its website that it could take days to rescue the man, who apparently fell in the Kita Gacesina caves in the Velebit national park.
The man, a speleologist, was not named.
The system of caves, which is located some 160 kilometres south-west of Zagreb and extends for more than 20 kilometres underground, is the largest in the Western Balkans.