Michael J. Sullivan, the U.S. attorney for Massachusetts, has convened a grand jury to investigate a broad array of trading abuses in the mutual fund industry, according to securities lawyers who have been informed of the probe.

The grand jury, active for more than a month, is looking at suspected trading abuses at the Boston office of Prudential Securities and a variety of issues involving market timing and late trading throughout the industry.

The investigation presents an opportunity to bring criminal charges in the growing national scandal, involving the unfair, lucrative trading of mutual funds by insiders and certain privileged clients.

“With all of the focus being on New York Attorney General Eliot Spitzer and Massachusetts Secretary of State William F. Galvin and the Securities and Exchange Commission, what is forgotten is the U.S. attorney is the only prosecutor with federal criminal jurisdiction,” said former federal prosecutor Jacob S. Frenkel, a partner at Smith Gambrell & Russell in Washington, D.C. “To the extent that there is securities fraud in the mutual fund activities, it’s squarely within his jurisdiction to prosecute it.”

Unlike the civil charges brought by the SEC, or administrative complaints filed by the secretary of state, U.S. prosecutors can bring criminal charges for which punishments include the possibility of jail time. Civil remedies typically include fines, censures, and in the extreme, a ban from the securities industry. Samantha Martin, a spokeswoman for Sullivan, said, “We can’t confirm or deny investigations.”

Yesterday, a judge sentenced James Connelly, former vice chairman of mutual fund firm Fred Alger Management Inc., to one to three years in prison, making Connelly the first executive to be sentenced in the fund scandal. Connelly in October pleaded guilty to criminal charges of evidence tampering as part of a probe into whether the company allowed illegal after-market trading of mutual fund shares

The Prudential investigation is being handled by assistant U.S. attorneys Jack Pirozzolo and Michael J. Pineault, according to several lawyers with knowledge of the effort. Pineault played a key role in former U.S. Attorney Donald K. Stern’s 2001 prosecution of violations of wheelchair access laws at local movie theaters.

The U.S. attorney’s office has requested information from Prudential Securities, Wachovia Securities, and Galvin’s office, according to several people familiar with the actions. Galvin, in an interview, confirmed that Sullivan requested information about Prudential Securities. Federal prosecutors have also issued a subpoena to Putnam Investments over trading in the company’s mutual fund shares. Putnam was charged with fraud by Galvin and the SEC in late October for allegedly allowing money managers to market time mutual funds they supervised.

Robert DeFillippo, a spokesman for Prudential, declined to say whether the company or its employees have received subpoenas from the grand jury. “We’re cooperating with all regulatory authorities,” he said. A spokesman for Wachovia would not comment on the U.S. attorney’s action, but said the company cooperates with all government investigations as a matter of policy.