With chants of "keep your hands off Hadleigh" protestors voiced their anger at plans for a store at the former Brett Works site.

Demonstrators marched along the riverside walk to highlight claims that a new superstore would ruin the area and threaten wildlife.

Police were forced to close High Street as the numbers swelled and spilt onto the road.

Patzi Shepperson, who lives in High Street, said: "This will give Tesco a bloody nose and send a clear message to keep out of the riverside area.

"The riverside is a place for families to enjoy fresh air, it's a breathing space. Four hundred cars an hour and lorries suddenly pouring into a supermarket will mark the end of this. Once it has gone, it has gone forever and it must be stopped for everyone's sake."

John Bloomfield, a member of the Hands off Hadleigh campaign group, which organised the march, said: "I'm absolutely delighted with today's turnout. Maybe this will show Tesco that it can't just steamroll into a town against the majority of people's wishes."

Plans for the store have been submitted to Babergh District Council, which sold the land to Tesco last year.

Mr Bloomfield said Babergh should make a decision for the people "rather than its own pockets". "That is what it's here for and quite clearly it should reject the proposals," he said.

Michael Kissman, Tesco corporate affairs manager, said the site was chosen by the council and a planning inspector.

"It was chosen by the best planning brains for a reason. Through public consultations we have come up with the best design which takes into account the impact on wildlife and will improve the area."

He said all the evidence proved that a Tesco close to a town centre would boost the local economy and benefit High Street shops.

But – dressed as the Grim Reaper for Saturday's march – resident Jan Devey said the site was a prime site for the community but not a supermarket.

She said: "Nothing could ruin this wonderful green area, filled with allotments and natural space, more than ripping it apart for a Tesco."

As the march reached the market square, Royden Smith stood as a lone pro-Tesco campaigner with "Tesco for Hadleigh," emblazoned on his hat.

He said: "What this lot are saying is a load of rubbish. I see lots of children here with their parents and a lot of misleading information has evidently brainwashed many people.