The Federal Communications Commission issued its largest fine in history against Texas-based telemarketers that transmitted approximately 1 billion robocalls to sell fake health insurance policies. The $225 million fine is part of the first major effort by acting FCC chairwoman Jessica Rosenworcel to stamp out illegal robocalls.

The agency alleges in a statement Wednesday that the telemarketers illegally spoofed phone numbers to sell short-term, limited duration health insurance plans, which falsely claimed to offer health insurance plans from well-known health insurance companies, such as Aetna, Blue Cross Blue Shield, Cigna, and UnitedHealth Group.

The move, which was announced at the FCC’s March meeting, is part of Chairwoman Rosenworcel’s first set of anti-robocall actions to combat unwanted robocalls.

The agency also delivered cease-and-desist letters to six voice providers that have consistently violated FCC guidelines on the use of autodialed and prerecorded voice message calls, the agency said. The FCC has also launched a Robocall Response Team, and it delivered letters to the Federal Trade Commission, Department of Justice, and the National Association of State Attorneys General to renew state-federal partnerships to combat the proliferation of illegal robocalls.

“Unwanted robocalls are not only a nuisance, but they also pose a serious risk to consumers who can inadvertently share sensitive, personal information in response to bad actors’ malicious schemes,” Rosenworcel said in a statement. “I’m proud to unveil my first set of actions to put a renewed focus on what the FCC can do to combat the issue that we receive the most complaints about.”

Rosenworcel said she believes it’s important for the FCC to coordinate within the agency and with other federal and state partners to combat the problem. She said that the the cease and desist letters along with the massive fine should serve as a warning to perpetrators that the FCC will take enforcement action.

Robocalls have been a persistent problem in the US. The coronavirus pandemic has served as fertile ground for illegal callers to take advantage of Americans by offering nonexistent medical equipment, fake testing kits for COVID-19, or for selling fake health insurance plans.

Rosenworcel is just the latest in a line of FCC chairs to vow to combat these annoying calls. Former FCC Chairman Tom Wheeler, who was appointed by President Barack Obama, introduced a series of initiatives aimed at stopping the robocalls. Former chair Ajit Pai, who served under President Donald Trump, also saw combatting robocalls as a main priority. In fact, the $225 million fine finalized and announced by the FCC today was proposed in June under Pai’s FCC.

Now, Rosenworcel says she will be getting tough on robocallers, too. The six companies receiving the cease-and-desist letters include three Canadian companies, RSCom, Stratics Networks, and Icon Global, along with a Florida based Yodel Technologies, UK-based Icon Global and New Jersey based IDT Corporation.

The letters sent to these voice providers to investigate and cease transmitting illegal robocalls immediately. The companies have also been instructed to take steps to prevent their networks from continuing to be sources of illegal robocalls.

The FCC has authorized voice providers that receive calls from these companies to block voice traffic if the warned providers do not take steps to effectively mitigate illegal traffic.

In addition to these actions, Rosenworcel has also established the FCC’s Robocall Response Team, which will consist of a group of 51 FCC staff members across six bureaus and offices tasked with coordinating and implementing the agency’s anti-robocall efforts.

“The Robocall Response Team will bring together Commission efforts to enforce the law against providers of illegal robocalls, develop new policies to authenticate calls and trace back illegal robocalls, and educate providers and other stakeholders about what they can do to help,” the FCC said in a press release.