"Although the international task force's work is far from complete, my suspicions have already been confirmed: The market for cryptocurrency investments is saturated with fraud, and our work is only revealing the tip of the iceberg," said Joseph Rotunda, director of enforcement at the Texas State Securities Board.

More than 40 state and provincial watchdogs are participating in "Operation Crypto-Sweep," which has triggered at least 70 investigations so far. The coordinated effort, first reported by The Washington Post , focuses on a cryptocurrency fundraising process known as initial coin offerings, as well as other "investment schemes."

Regulators in the U.S. and Canada are launching a widespread crackdown on some cryptocurrency investment schemes, members of the North American Securities Administrators Association said Monday.

Earlier in May, Texas regulators sent a warning letter to U.K.- based BTCrush saying it was violating securities laws and misleading investors through its marketing. The company published videos showing the interior and workings of what it said was three fully operating mining farms. State regulators said the videos were actually sourced from publicly available stock footage.

The Texas regulator also took action against Wind Wide Coin, which used pictures of celebrities including Jennifer Aniston and Prince Charles to advertise its cryptocurrency.

"Promoters also know that anyone can be anyone and say anything about anything on the internet," Rotunda said. "Not surprisingly, they are also manipulating photographs, media, testimonials and other online information to deceive the public into believing their claims."

The crackdown comes amid growing attention in the U.S. to cryptocurrency scams, including by the Securities and Exchange Commission and the Commodity Futures Trading Commission. The SEC has brought several fraud cases against operators of initial coin offerings and last week launched a website to help investors recognize scams.

Massachusetts regulators are also participating in the crackdown.

William Francis Galvin, the state's secretary of the commonwealth, said NASAA's task force found roughly 30,000 crypto-related domain name registrations, many of which appeared in late 2017 as the price of bitcoin neared $20,000.

"Not every ICO or cryptocurrency-related investment is fraudulent, but we urge investors to approach any initial coin offering or cryptocurrency-related investment product with extreme caution," Galvin said in a statement. "Fraudulent activity involving ICOs and cryptocurrency-related investment products is a serious threat to Massachusetts investors."