PHILADELPHIA — Two years ago, a federal prosecutor in Pittsburgh considered filing a racketeering lawsuit against a Roman Catholic diocese over its handling of child sex-abuse complaints, but left office before he could make the bold move.

A colleague in Philadelphia is now taking new aim at the church, sending grand jury subpoenas to dioceses throughout Pennsylvania as he tries to build a federal criminal case centered on the wholesale exploitation of children.

U.S. Attorney William McSwain of Philadelphia has a head start on the work, given the sweeping state grand jury report released this summer, which found that 301 priests molested more than 1,000 children over seven decades. McSwain, a Harvard Law School graduate and former Marine sniper platoon commander, was appointed by President Trump and took office just four months ago.

All but one of the state’s eight dioceses confirmed Thursday that they have received the federal subpoenas sent last week, and largely sounded willing to comply. Meanwhile, the Buffalo Diocese in upstate New York has confirmed that it responded to a federal subpoena months ago by turning over requested documents.

“This is a monumental moment for clergy sexual victims everywhere,” said Mitchell Garabedian, the Boston-based plaintiffs’ lawyer who played a major role in uncovering the scandal in the Boston Archdiocese in 2002.

“Pope Francis has to be deeply concerned about what the federal investigation will reveal within the Diocese of Buffalo,” Garabedian said. “The federal investigation represents hope for clergy sexual abuse victims in all of Buffalo and also worldwide.”

There’s no sign the Buffalo probe is related to the investigation launched by McSwain, who only took office in June, or that the Justice Department wants to pursue a national review of clergy abuse complaints.

McSwain, among other things, wants to know if any priests took children across state lines for sex; viewed child pornography; reassigned predators; or used church funds or assets to cover up sexual misconduct. He has demanded the church turn over files from any “Secret Archives,” along with financial, personnel and treatment records. And he expects to take testimony from church leaders.

The federal government’s intervention opens a new front of legal peril for the church, given that investigations into sexual abuse by clergy members have historically been handled by state and local authorities.

Church officials across the state — in Philadelphia, Pittsburgh, Scranton, Erie, Greensburg, Allentown and Harrisburg — said on Thursday they would cooperate or were working with Justice Department officials.

“This subpoena is no surprise considering the horrific misconduct detailed in the statewide grand jury report,” the Greensburg Diocese said in a statement. “Survivors, parishioners and the public want to see proof that every diocese has taken sweeping, decisive and impactful action to make children safer. We see this as another opportunity for the Diocese of Greensburg to be transparent.”

It could be months before the grand jury hears testimony because of the time it takes to review the cache of requested documents. McSwain wants to know if any priests, bishops, seminarians or others committed any federal crimes.

He also demanded that bishops turn over evidence that anyone in their ranks instructed anyone not to contact police. The subpoenas seek documents related to the dioceses’ organization, finances, insurance and clergy assignments.

A representative for McSwain declined to comment, as did a Justice Department spokeswoman.

Two Eastern Catholic dioceses in Pennsylvania — the Ukrainian Catholic Archeparchy of Philadelphia and the Byzantine Archeparchy of Pittsburgh — also acknowledged they are under investigation.

“I’m thrilled at hearing this information. We have the full weight and attention of the United States federal government investigating the Roman Catholic Church,” said Shaun Dougherty, 48, of Johnstown, who told authorities he was molested by a priest as a boy in the Altoona-Johnstown Diocese.

While the subpoenas hint at possible charges of sexual exploitation of minors and fraud, legal experts said that if federal prosecutors can show that church leaders systematically covered up for child-molesting priests in the past five years, dioceses could also be charged under the Racketeer Influenced and Corrupt Organizations Act, or RICO, the law originally passed to bring down the Mafia. David Hickton, the former U.S. attorney in Pittsburgh, looked at bringing a criminal or civil RICO case against the Altoona-Johnstown Diocese in 2016, but ran out of time when he left office upon Trump’s election.

The nearly 900-page Pennsylvania grand jury report this summer found that church leaders had engaged in a systematic cover-up by shuffling accused priests around to different parishes and in some cases working to prevent police investigations. Most of the complaints were decades old, and because of the statute of limitations, only two priests were charged as a result. Many other priests are dead.