A 20-year-old man from south London has been arrested on suspicion of murder after a woman was fatally stabbed on a beach in Bournemouth, police have said.

Two women from Poole in Dorset were stabbed on Durley Chine beach at about 11.45pm last Friday. A 34-year-old woman died at the scene while a 38-year-old woman sustained serious injuries and remains in hospital.

The suspect is from Croydon and has also been arrested on suspicion of attempted murder, Dorset police said on Tuesday. The force added that intelligence and firearms officers worked with the Metropolitan police to arrest the man in London.

The woman who was stabbed to death was named locally as Amie Gray, a sports coach who was described as a beloved mother, wife and friend. Family and friends paid tribute to Gray, who was the women’s head coach at Dorset futsal club.

Dorset futsal club posted on its Facebook page: “The club has received some truly devastating news. We cannot put this into words at this time and as a mark of respect to all those affected, we will not be posting anything new for the foreseeable future.”

A friend of Gray wrote on social media: “She was always the kindest lovely young girl and continued to be so throughout her cruelly cut short life.”

Another said: “Fly high, Amie Gray, I’ll miss you so much. I feel so heavy! You were such a good friend and someone I could call about anything. A beautiful person inside and out. Thank you for all the laughs and memories I will cherish for ever.” A third added: “You lit up the room with your fun and bubbly presence.”

Floral tributes have been left at both ends of the mile-long police cordon. A 17-year-old boy who was arrested on suspicion of her murder was released without charge.