Kirsty Bentley's mother is welcoming news police are offering a 100 thousand dollar reward for information on the Ashburton teen's death

The 15-year-old was last seen walking her dog on the afternoon of December 31, 1998.

Jill Peachey says it's 'great' Police are offering the reward to try and find her daughter's killer, but she doesn't want to comment further.

Police say they're looking for material information or evidence leading to the identity and conviction of the person or people responsible.

Kirsty's body was found in Rakaia Gorge two weeks after she disappeared.