The families of victims and survivors of one of the UK’s worst fairground disasters have called for improved support for children who have suffered trauma as they marked the 50th anniversary of the tragedy.

Five children were killed and 13 injured on May 30 1972, when the Big Dipper rollercoaster crashed in Battersea Park, south-west London.

Liz Haigh-Reeve, who was 15 when she was injured in the accident, said she was “shocked” that support for child trauma victims did not seem to have improved in the past 50 years.

Friends and family of victims and survivors met on Monday to remember the victims at the site where the tragedy took place.

They were joined by Marsha de Cordova, Labour MP for Battersea, and Wandsworth mayor Jeremy Ambache, who planted a cherry tree in memory of the five who were killed.

Loved ones lay flowers at the foot of the tree, which it is hoped will blossom each year at the end of May to coincide with the anniversary.

A relative of each of the victims gave a speech in honour of those who died – the youngest, Shirley Nash, was just eight – followed by a minute’s silence.

Christine Nicholas, sister of David Sait, who also died in the accident, said: “I miss the boy he was and the man he should have become. I miss that my children and grandchildren never knew him.

“When he left that morning 50 years ago, I offered him my cheek and said, ‘kiss me goodbye then’. I didn’t really expect him to, as teenagers don’t usually kiss each other. But he kissed my cheek with a grin and off he went.

“I never saw him again.”

The site of the ride is now covered with tarmac, and though there were signs explaining there used to be a funfair in Battersea Park, there had been no mention of the event and the loss of life in the park before Monday’s event.

Liz Haigh-Reeve went on the Big Dipper for her 15th birthday in 1972 alongside friend Alison Comerford, who died in the accident. Ms Haigh-Reeve suffered injuries to her arm and hand.

She told the PA news agency: “It’s been amazing to see so many people who were a part of this day that I’d never seen and haven’t spoken to and have shared the experience that I’ve shared, and it’s really brilliant to see something is being done.

“It’s been emotional and it’s been tough, but it’s also been a comfort. I think it’ll be a healing day.”

She continues to campaign for a permanent memorial in Battersea Park, as well as for the improvement of mental health services for children who suffer serious trauma.

In her speech at the memorial event, she said: “I’ve been shocked to discover that 50 years on, if anything, the provision of support for children who’ve suffered trauma is even more limited than it was in 1972. We cannot allow this to continue.”

Ms De Cordova backed the campaign, telling PA: “I believe it’s the start of a new chapter. Essentially, we want to get a permanent memorial here in Battersea Park.

“Going forward, we want to ensure that there are proper services and proper support for young people.”

During the inquiry into the tragedy, it emerged that there were 66 faults with the Big Dipper, which had been built for the Festival of Britain in 1951.

London mayor Sadiq Khan is among those who have voiced support for a permanent memorial in the park.