Police are reviewing footage of a man at Putney Bridge station after the Crimewatch presenter was shot in 1999.
Jill Dando's legacy continues as Good News Rooms are introduced in more schools and a blue plaque is unveiled in her name.
The scheme, created in memory of murdered journalist Jill Dando, is being taken worldwide.
Jill Dando News Centres were launched at her former school and now teach students in Africa.
Jill's older brother Nigel says she continues to be an "inspirational figure" for all.
The late star's brother hopes a new docuseries, Who Killed Jill Dando?, will jog somebody's memory.
A replacement memorial has been unveiled after a previous tree was mistakenly cut down.
