A young girl has died and another is in a critical condition after a tree fell in a seaside park in Essex on Saturday.

The girls, aged seven and six, suffered serious injuries and were taken to hospital. Police said the seven-year-old girl died in hospital.

Three other children suffered minor injuries following the incident in Southend-on-Sea.

Essex police said they were called to Chalkwell park shortly before 3pm, where they found “a number of casualties”.

Ch supt Leighton Hammett said: “Families are facing unimaginable hardship this evening and all of our thoughts are with them at this time.

“I cannot begin to put into words how difficult today’s events have been, and continue to be, for them.

“It’s also not lost on me how traumatic it must have been for the members of the public who witnessed this awful incident.”

An East of England ambulance service spokesperson had earlier said: “Two children were transported by road to Southend university hospital.

“A further three children were later transported by road to the same hospital with minor injuries.”

Police advised the public to avoid the area.

Ishan Madan, 39, from Westcliff-on-Sea, was playing in a cricket match nearby when he heard a “horrendous, screeching scream”.

Madan, an accountant, said: “Everyone ran towards the clubhouse, where the tree is.

“The tree had snapped and I think there were four children, the fifth one was slightly further away, I think she’d been hit by a branch.

“Two of them were under a smaller branch, they were rescued easily, and unfortunately, the other two girls, they were stuck under this massive tree.

“So we got bystanders to help, it must have been 40 to 50 people who then tried to lift the fallen tree up and to our horror, these two little girls, poor girls, were stuck underneath it.

“Their mother was on the corner. It was horrendous.”

Adam Hutchins, 47, told the EssexLive website: “I heard there were kids playing on the tree. They heard a big crack.

“It must have [been] pretty loud. They went running over and there were kids underneath the tree.

“All the cricket guys ran over and tried to loft the tree up. I think it’s one of the oldest trees. It had metal stands propping it up.”

David Burton-Sampson, Labour MP for Southend West and Leigh, said: “The news of the sad death of one of the children involved in the incident at Chalkwell park today is truly devastating.

“I am sure I reflect the thoughts of all our residents here in Southend in sending my deepest condolences to the child’s family and friends.

“My thoughts are also with the other children injured and I wish them a full and speedy recovery.

“At the time of the incident, the park was very busy and a number of people witnessed what happened.”

Daniel Cowan, the leader of Southend’s city council, said on Saturday: “I’m aware of this very serious incident. We’re working with Essex police, the ambulance service and fire service, who are still at the scene.

“I do understand that a tree has fallen, there’s a number of casualties and we’re just asking the public to avoid the area while those services carry out their work, and my thoughts are with those affected.”