A girl was airlifted to hospital after collapsing at a trampoline park.

GraVity Trampoline Park at Bluewater was shut on Sunday, with witnesses reporting lots of police on site.

Officers were called at 11.50am and arrived as ambulance crews were treating the girl, whose age is not yet known.

She was taken by the air ambulance to Kings College Hospital in London in a serious condition.

It's thought an unconnected birthday party at the site was cancelled.

A statement on GraVity's website today said: "Due to unforeseen circumstances the park is closed for the rest of the day."

The centre opened in December last year, as the company's new flagship centre.

The 25,000sq ft play area has the world’s first two-storey obstacle adventure course, an open bounce area and an urban climbing wall.

The adventure course features moving staircases, rotating floors and spinning punch bags.

The company also has a branch at Lockmeadow in Maidstone.

A GraVity Trampoline Parks statement said: "On Sunday, July 15 at our Bluewater Park, the GraVity Team attended to assist a collapsed customer in the early afternoon.

"Due to the medical incident, we made the decision to keep our site closed for the remainder of the day to conduct a thorough investigation.

"We are currently liaising with the relevant authorities to ensure they have everything they need to ascertain the facts surrounding the incident and we will release a full statement as soon as all facts have been established.

"For now, we would like to assure everyone that our Bluewater Park is open for business and operating as normal.

"No further bookings or available sessions are expected to be affected.

"Our thoughts are with the family and friends of the effected customer at this moment and we will be doing everything we can to help in this situation."