The US has filed lawsuits against five companies and three individuals over the hundreds of millions of fake robocalls made to American consumers from abroad, mostly from India, that caused massive financial losses to the elderly and vulnerable.

The department of justice has alleged in its class action lawsuit that the accused companies had ignored multiple warnings against fraudulent robocalls — including government and business-impostor calls —and facilitated foreign-based fraud schemes targeting Americans.

It has sought a restraining order against the defendants, whom it accused of serving as “gateway carriers”, making them the entry point for foreign-initiated calls into the US telecommunications system.

“The calls, most of which originated in India, led to massive financial losses to elderly and vulnerable victims across the nation,” the justice department said on Tuesday.

The calls falsely threatened the victims with a variety of catastrophic government actions, including the termination of social security benefits, imminent arrest for alleged tax fraud and deportation for supposed failure to fill out immigration forms correctly, the justice department said.

“Each of these claims is a lie, designed to scare the call recipient into paying large sums of money,” it said.

One case has been filed against Ecommerce National LLC d/b/a TollFreeDeals.com and SIP Retail d/b/a sipretail.com; as well as their owners/operators: Nicholas Palumbo, 38, and Natasha Palumbo, 33, of Scottsdale, Arizona.

The other case has been filed against Global Voicecom Inc, Global Telecommunication Services Inc, KAT Telecom Inc (aka IP Dish) and the owner/operator Jon Kahen, 45, of Great Neck, New York.

In each case, the justice department has sought an order immediately halting the defendants’ transmission of unlawful robocall traffic. A federal court has entered a temporary restraining order against the Global Voicecom defendants.

The justice department said: “Social security impostors, IRS (inland revenue) impostors, and tech-support schemes (in which callers impersonate legitimate technology companies) have proliferated in part because of the ease with which robocalls can reach millions of potential victims every hour.”

In the cases announced on Tuesday, the US has alleged that the defendants operated voice over internet protocol (VoIP) carriers, which use an Internet connection rather than traditional copper phone lines to carry telephone calls.

Numerous foreign-based criminal organisations are alleged to have used the defendants’ VoIP carrier services to pass fraudulent government-and business-impostor fraud robocalls to American victims.

According to the justice department, the defendants carried astronomical numbers of robocalls.

For example, the complaint against the owners/operators of Ecommerce National d/b/a TollFreeDeals.com alleges that the defendants carried 720 million calls during a sample 23-day period, and that more than 425 million of those calls lasted less than one second, indicating they were robocalls. The complaint alleges that many of the 720 million calls were fraudulent.