Temporary space used by connected sessions (oracle 10g)

select
        tablespace_name,
        current_users,
        total_extents,
        used_extents,
        free_extents,
        max_used_size,
        max_sort_size
from
        sys.v_$sort_segment
order by 1;  

Temporary space storage issue like large disk sorts can cause out of space conditions.
Query shows that users are currently using space in temporary tablespace.