AMESBURY — Just weeks before launching the region's first "Zorb ball" attraction, Amesbury Sports Park has abruptly dropped the company that was set to implement the activity after discovering its founders were involved in a bizarre "buried treasure" case that grabbed national attention.

The sports park has planned an extensive grand opening to promote the launch of the Northeast's first Zorb ball park — a hugely popular activity in New Zealand and overseas — where participants climb inside a giant, clear, inflatable ball and roll down a hill.

Park officials told The Daily News they planned to partner with Barry Billcliff and Matt Ingham of Zorb New England, who were going to provide the park with five Zorb balls, each costing $10,000 apiece. The pair would give exclusive rights guaranteeing no other facility within 70 miles of Amesbury could use Zorb balls from Zorb New England. It was to be Zorb New England's debut as well.

But park management abruptly reversed course shortly after a media demonstration at Woodsom Farm this week, when questions were raised about Billcliff and Ingham's involvement in a well-publicized 2005 case of alleged larceny of antique money from a Newbury barn.

"Amesbury Sports Park has decided not to sign an LLC with Zorb New England as of last night," Sports Park Vice President Mary Carol Fowler told The Daily News yesterday, adding the park had no prior knowledge of the 2005 case and that she was "stunned" to learn of it.

Zorb ball and a summer tubing program are still planned to start in June, she said, but the facility will find another vendor for the Zorb balls.

Billcliff, of Manchester, N.H., and a friend, Tim Crebase of Methuen, made national headlines in 2005 after claiming to have found $720,000 in antique money buried in the backyard of a friend's home in Methuen. They went on a media blitz, appearing on shows such as Good Morning America and CNN with their amazing story of buried treasure.

But within days, inconsistencies appeared in their stories, and Methuen police charged Billcliff and Crebase with stealing the antique money. They were arrested shortly before they were to appear on Jimmy Kimmel Live.

Police said Crebase and Billcliff found 1,800 rare bills, dated from 1899 to 1928, stashed long ago in the eaves of Sylvia Littlefield's Newbury barn. They had been hired to do roofing work on the building.

Police believed the two then convinced Kevin Kozak of Methuen, and Ingham of Newton, N.H., to say the money was discovered while doing landscaping work in Kozak's backyard in late April 2005.

The accused men have publicly denied that they stole the bills, and the criminal charges were dropped in February 2006 after defense attorneys questioned the validity of a confession Crebase made to police. In February 2007, Newbury police tried to refile charges in Newburyport District Court, but the attempt was denied because a judge said the defendants had been denied a speedy trial.

But Littlefield has filed a civil case against Billcliff and Crebase and two friends, including Ingham. A trial date is still pending in that case, Littlefield said this week.

Billcliff, who helped organize the media event this week and posed for photos in a Zorb ball, initially asked that The Daily News not mention that he was involved in the Zorb ball company, which the newspaper refused to do.

When reached on his cell phone last night, Billcliff acknowledged the contract had been severed with Amesbury Sports Park, but said he would press on with his company. He said has long-range plans and sees it as a way to pursue something he enjoys.

"The biggest thing I want to do is put an American twist on it," he said. Billcliff said his company has a goal to bring zorbing to several facilities in each state and offer it a price far less than anywhere else in the world — closer to $10 to $20 per ride, which is half the price of zorbing in other countries.

Billcliff said he also is working with a company in Newton, N.H., to expand on zorbing by adding more features — like cameras inside the balls to take photographs. Other projects include adding balls that can be used in waterfalls or to cross a lake, he said.

"The sky is the limit," Billcliff said.