PREVIEW

Figen Murray, mother of Manchester Arena bombing victim Martyn Hett, arrives in Downing Street, London with (left to right) husband Stuart Murray, and daughters Nikita Murray and Louise Webster, to hand in a letter about Martyn's Law to Number 10, after her 200-mile walk to London from the spot where her son was killed in Manchester.

Martyn's Law is named in tribute to the 29-year-old who was one of 22 people killed at the end of an Ariana Grande concert in May 2017, would require venues and local authorities in the UK to have preventative plans against terror attacks