Fifteen people fell ill with cryptosporidiosis linked to the type found in Northampton's tap water after a parasite was found at the Pitsford Water Treatment Works in June.

The source of the parasite was linked to a rabbit found in a tank at the treatment works.

Several newspapers and a number of websites have since speculated the rabbit could have been planted on purpose, but Anglian Water has dismissed the idea.

Andrew Mackintosh, head of group communications for the water firm, said it was more likely the rabbit got into contact with the water through a number of "freak circumstances".

He said: "We cannot draw any conclusions at all from anything.

"It could have been extremely freak circumstances, it could have been anything. We just do not know at this stage."

As previously reported in the Chron, Anglian Water has passed information about the cryptosporidium outbreak to the Drinking Water Inspectorate, who will carry out an investigation.

The circumstances surrounding how the rabbit got into the tank will form part of this.

Ultra-violet treatment was used to clean water at Pitsford following the outbreak, with the treatment so successful the boil notice was lifted ahead of early indications.

When cryptosporidium was detected in June it was the first time since the water treatment works had been built 50 years ago.

While the boil notice was in place, Anglian Water delivered bottled water to schools, hospitals and nursing homes.

Vulnerable customers were also given water, with the WaterCare Register swelling to more than 3,000 customers.

Goodwill payments to compensate customers for the inconvenience are now being calculated, with some people opting for the money to go to charity.