Federal regulators on Wednesday charged Gary J. Martel, the former Chelsea broker, with defrauding investors and froze his assets.

The Securities and Exchange Commission said Martel – a former planning board member for the city of Chelsea – had taken at least $1.6 million from more than a dozen investors in Massachusetts, Vermont and Florida over six years. The SEC’s complaint followed civil fraud charges brought against Martel last week by Massachusetts Secretary of State William F. Galvin.

According to the SEC’s complaint, Martel was selling “pass-through bonds” to investors, including a number of family members and retirees, ensuring them they were safe. Martel also allegedly offered other fraudulent investments, such as access to shares of Facebook Inc.’s recent stock offering.

Martel’s lawyer has said that the broker denies wrongdoing. She could not immediately be reached for comment late Thursday.

Martel allegedly used three entities to conduct business, none of which was registered to sell securities. They were Martel Financial Services and MFG Funding, both of Chelsea, and Martel Financial Group of Woburn and Chelsea. Public records also associate Martel with two mortgage offices in recent years: Mass Mortgage Capital Group and Allied Home Mortgage Capital.