Hartford — U.S. Sen. Richard Blumenthal appeared Tuesday at the Legislative Office Building alongside three former Eversource Energy employees to decry abuses of the H1-B visa program that led to the loss of 200 American information-technology jobs at the Massachusetts-based company two years ago.

Blumenthal called on Eversource, formerly known as Northeast Utilities, to restore the jobs of those he said were forced out as well as rescind a non-disparagement agreement departing workers were forced to sign to get severance pay.

The Connecticut Democrat said the agreement has acted as a muzzle for most employees, who have felt constrained from telling the public about their mistreatment, which included being forced to train foreign workers to replace them.

Eversource, however, said it has not violated any laws and said there is no "gag order" in place constraining former employees from talking about the reorganization of the company's information technology department.

"These were state reviewed organizational changes made two and a half years ago to streamline the operations of our newly merged company and better serve our customers," Eversource spokesman Al Lara said in an email.

Craig Diangelo of New Britain, a 15-year former employee of Eversource who was among those to sign the non-disparagement agreement, spoke out during the news conference, saying he wanted to end the epidemic of H1-B visa holders being used by corporations to replace American workers and save money.

"To me, this is corporate blackmail at its worst," Diangelo said of the agreement he was forced to sign to get a severance.

Diangelo said American workers found foreign replacements to be of a much lower skill level than their American counterparts — as evidenced by the 10 weeks' extra severance Americans were offered to extend their training of replacements from January to May 2014.

"Those were the longest and hardest five months of my life," Diangelo said. "I lost my work family, and I lost my job."

Diangelo said American workers started placing U.S. flags near their work stations in silent protest over the situation.

"The flags disappeared as we did," he said.

Blumenthal said he recently wrote to Thomas May, chief executive of Eversource, to allege that its program to replace American workers in a systematic outsourcing effort apparently was an abuse of several visa programs, including the H-1B, which originally was intended to allow workers with very specialized skills to enter the country.

Amendments to the law, according to H-1B activists, have since watered down the original intent so that even foreign workers with ordinary skills can legally replace Americans with the same or better skills.

Eversource, in a reply to Blumenthal's accusations, said that alleged H-1B abuses "did not take place at Eversource Energy." The company admitted saving $18 million by employing a new IT platform using employees contracted from Infosys and Tata Consulting Services, but said the new model was reviewed by state regulators who found it did not place consumers at risk for poor service or security issues.

Blumenthal, who has asked the U.S. attorney general's office to investigate potential violations by Eversource, said he hopes to change the worker-visa law so that it reverts to its original intent by passing a bipartisan piece of legislation called the H-1B and L-1 Visa Reform Act of 2015.

The bill would require a good-faith effort to hire American workers before allowing companies to look overseas.

"This program, although well intentioned, is rampantly abused," Blumenthal said during the news conference. "This situation cries out for reform."

Sara Blackwell, a Florida-based attorney who represents dozens of displaced workers nationwide, said the use of H-1B visas has become a business model for corporations looking to save money by hiring younger foreign workers at significant savings.

Eversource, she said, is one of many companies nationwide to employ the strategy, with other recent examples including IBM, Abbott Labs and Disney.

In addition, the American information-technology force at Pfizer Inc. in Groton and New London was replaced nearly a decade ago using the same H-1B outsourcing strategy.

Contractors at the time said they were being replaced largely by information-technology workers from India.

"My goal is to get Americans to stand up," Blackwell said in an interview before the news conference. "Americans don't know this has been happening for 15 years."

She estimated that hundreds of thousands of Americans have lost their jobs because of the misuse of the H-1B program.

Blumenthal said the program is not all bad. In fact, he has advocated for expansion of such visas for institutions such as the Connecticut Medical Center and Yale-New Haven Hospital.

But the abuse of the system is potentially putting all of the legitimate H-1B visa uses at risk, he said.

And for American workers forced out of their jobs, many in their 40s and 50s, the stark reality is that it is hard to find a new position at the same pay.

Diangelo has found a temporary contract job at less pay and with few benefits, but others became so specialized in what they had done at Eversource that it is difficult to find work, Blackwell said.

"The saddest part is my job is still there but I am not," Diangelo said.

l.howard@theday.com

This article has been edited to add comments from Eversource.