FITCHBURG, Wis. -- The race for mayor in Fitchburg is heating up after one of the candidates put out a fundraising letter that alleges his opponent has ties to a domestic "terrorist" group.

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The candidate who put out the mailer, former Mayor Mark Vivian, said he's being accurate and drawing attention to differences.

But Jay Allen, a Fitchburg City Council member and the mayoral candidate attacked in the mailer, said the letter's claim is nothing less than shocking.

"I don't have any ties to terrorist groups. I don't know about any terrorist groups. I've never met a terrorist that I know of," Allen said. "I don't know, maybe what's happening against me could be considered some form of terrorism."

Allen said he was recently informed of a mailer sent out by his opponent.

"I think it's bizarre. I think it's the strangest turn of events that I could ever have imagined," Allen said.

"The purpose of the letter was to get people's attention and to illustrate my differences between myself and my opponent," Vivian said.

The issue concerns a piece of land in Fitchburg, the Novation campus, which is being developed there by the Alexander Co., the Drumlin Community Garden and a historic house.

Allen said he was trying to save the building and the farm by starting imminent domain proceedings.

Vivian disagrees with the tactic, and his mailer said not only that, but also that the current tenants of the house have ties to a domestic terrorist group.

"I was simply pointing out the groups that he's associating with, or perhaps he doesn't know that he's associating with, that have no legitimate claims to this issue in Fitchburg," Vivian said.

Vivian is referring to a group called "Food Not Bombs," which helped organize a protest meal outside an Alexander Company building with the Friends of Drumlin.

Food Not Bombs in some areas of the country has been investigated as a terrorist group but primarily is an organization that recovers food that would be thrown out and serves vegetarian meals to the homeless.

"It's not inaccurate, and that's the point I'm trying to make, and I think the focus has been too much on the words 'terrorist watch group' and not enough on the use of condemnation," Vivian said.

But Allen said the allegations speak for themselves.

"Whether it sways any votes or not, it's up to the voters to decide whether this is the type of mud they want slung around their city," Allen said.

Allen said he hadn't ever heard of Food Not Bombs and pointed out he tabled his resolution for imminent domain once Alexander Company came to the table last month for negotiations on the property.

Vivian said even if the company is now willing to sell, he thinks it would be a bad precedent for neighborhood planning in the city to be buying up green space.