Dr. William Petit is blasting a political ad Wednesday that urged voters to "Stop Donald Trump and Republican William Petit's attack on women and families."

Petit is the GOP candidate vying for Connecticut's State House of Representatives in the 22nd District, representing parts of Plainville and New Britain. He was the sole survivor of the 2007 Cheshire home invasion in which his wife Jennifer and daughters Hayley and Michaela were murdered.

"To post something that says I attack women and families I thought was about the lowest of blows," he said.

In a news conference on Wednesday, Petit called the ad libelous and pointed to his work with the Petit Family Foundation, an organization set up after he lost his family.

"I've worked over the past nine years to honor the memory of my family and the whole mission of what we do. We've tried to come up with programs we felt would honor Jennifer, Hayley and Michaela, would be things that they would want us to do," Petit said during a news conference on Wednesday. "For a shadowy political organization to blatantly ignore that work and publish a despicable ad is reckless and incomprehensible."

The ad was the work of a political action committee called Labor United for Connecticut, according to Themis Klarides, House Minority Leader in Connecticut.

The ad even drew criticism from Petit's opponent, Democratic incumbent Betty Boukus.

"I am horrified by the tasteless and offensive attack ad against my opponent. It was produced by a third party with no connection to my campaign, without my knowledge, and without the involvement of anyone associated with my campaign," Boukus said in a statement on Wednesday. "I am asking those responsible to pull the ad and issue and apology to Dr. Petit and his family."

Boukus was in attendance at Dr. Petit's news conference on Wednesday.

NBC Connecticut reached out to Paul Filson, the head of Labor United for Connecticut, but we have not received a response.

Filson told the Hartford Courant: "We can only imagine the pain that Petit has gone through, and would never target his loss for our political agenda. It is not intended to reference any personal history. The Facebook post in question holds numerous Connecticut Republicans accountable for their support of Donald Trump and his policies, which independent experts have found to be harmful to women and middle class families."

Petit did not say he supported Trump during Wednesday's news conference. He said he would make a decision on who to vote for when he gets in the voting booth.