Involved in DNA double-strand break (DSB) repair (By similarity). Acts probably with HerA to stimulate resection of the 5' strand and produce the long 3' single-strand that is required for RadA loading (By similarity). Exhibits both single-stranded endonuclease activity and 5'-3' exonuclease activity on single-stranded and double-stranded DNA (PubMed:18194801). The 5'-3' ssDNA and dsDNA exonuclease and ssDNA endonuclease activities are inhibited by SSB. Homodimer (PubMed:21197557). Interacts with the single-stranded DNA-binding protein (SSB) (PubMed:18194801). The C-terminus is required for interaction with SSB. Belongs to the NurA family.