When news broke Tuesday that George E. Norcross III had been under federal investigation, the lawyer for the South Jersey Democratic power broker touted a letter from federal prosecutors in New Jersey that said they had ended their scrutiny of his client during a probe into state-approved tax credits.

But documents reviewed by the Inquirer and Daily News show that the 2016 wiretaps on Norcross' cell and work phones weren't tied to the New Jersey probe, but to a separate one on the other side of the Delaware River: the long-running investigation of Philadelphia labor leader John "Johnny Doc" Dougherty.

The documents — court filings related to the confidential wiretapping two years ago of both men's phones — were signed by the same prosecutor, authorized by the same judge, and bear identical case numbers.

What drew investigators' attention to Norcross remains unclear. But the records indicate for the first time a connection between the FBI's interest into perhaps the preeminent nonelected figure in Democratic politics in Pennsylvania and the man who holds the same kind of clout in New Jersey.

A spokesperson for the U.S. Attorney's Office for the Eastern District of Pennsylvania refused Wednesday to confirm or deny that the office had ever investigated Dougherty or Norcross.

Norcross' lawyer, Michael Critchley, told Politico on Tuesday that he had received assurances from Assistant U.S. Attorney Frank Costello, the Philadelphia-based prosecutor leading the Dougherty probe, that Norcross was not currently under investigation by his office. Critchley declined to comment Wednesday.

A lawyer for Dougherty said he was unaware until contacted by a reporter Wednesday that Norcross' phones had been tapped in connection with the investigation of the Electricians union.

"To the extent that that's the case, we certainly weren't aware that his were among the phones being intercepted," said defense attorney Henry E. Hockeimer Jr.

Dougherty and Norcross, through their representatives, have more than once denied any wrongdoing. Still, any connection between the men wouldn't surprise those who follow local politics.

Dougherty, 58, took command of Local 98 of the International Brotherhood of Electrical Workers in 1993, and in 2015 he became the head of the Philadelphia Building and Construction Trades Council, which represents nearly 40 unions in Philadelphia and the suburbs.

In his 25 years at the helm of his union, he has built the 4,700-member organization into a potent political force, placing numerous Democratic allies in elected and appointed municipal positions, and amassing one of Pennsylvania's biggest campaign war chests. In the last 18 months or so, its members have donated nearly a half-million dollars just to congressional candidates and causes in the region.

Norcross, 62, has played a similar role as a political kingmaker in New Jersey.

A Cherry Hill resident, insurance brokerage chairman, and chair of the board of Cooper Health System, he has been an economic and political force across the state for years. He has held sway over the largest, and thus most influential, bloc of state lawmakers in New Jersey.

At times, the men have combined their political clout toward shared goals. Both were involved in planning the 2016 Democratic National Convention in Philadelphia and worked the previous year to elect Jim Kenney mayor of Philadelphia.

Last month, investigators in Philadelphia notified people whose conversations with Norcross were caught on the FBI wiretap of his work and cellphones.

According to those documents, called intercept letters, the secret recordings began in July 2016, more than a year after investigators began listening to Dougherty's phones as well as those of other current and former Local 98 officials, including City Councilman Bobby Henon and union political director Marita Crawford.

The wiretaps shut down on Aug. 26, 2016 — three weeks after the probe of the union leader burst into public view with raids on the Local 98 union hall and more than a dozen other locations linked to Dougherty or other union leaders.

Search warrants from those raids – obtained by the Inquirer and Daily News last year —  suggest FBI agents have spent months poring over seized records pertaining to Local 98's activities, Dougherty's personal finances, and the role of dozens of union officials, contractors, political consultants, and Dougherty family members with ties to union work.

Possible charges include embezzlement, attempted extortion of contractors, fraud, tax evasion, and honest services fraud by public officials, the legal documents say.

And sources have indicated that the investigation bears the hallmarks of a racketeering conspiracy case, scrutinizing the levers by which Dougherty and his union exert their clout.

Those same sources, who were not authorized to discuss the case publicly, have also said that since the wiretaps concluded, the focus of the probe has shifted toward how Local 98 spent its funds than its involvement in politics.

While the Dougherty wiretaps went silent in 2016, the Norcross wiretaps resumed in October of that year and continued for about a month, the intercept letters show. But if that marked an entirely new investigation or was simply an outgrowth was unclear.

Critchley on Tuesday disclosed that federal prosecutors in New Jersey had taken an interest in his client around the same time that FBI agents in Philadelphia were monitoring his client's phone.

He also shared a Sept. 27 letter issued by the U.S. Attorney's Office in New Jersey that referenced an investigation tied to Norcross and the "procurement of tax credits" — one prosecutors in it declared to be closed. A spokesperson for that office would not elaborate Tuesday on the nature of that probe.

In 2013, Norcross and his allies in the Legislature had worked with then-Gov. Chris Christie to overhaul New Jersey's economic incentives programs. Under the law, the state has awarded billions of dollars in tax credits to companies that moved to or remained in New Jersey.

Norcross' insurance firm, Conner Strong & Buckelew, was among the companies awarded incentives to relocate to Camden. His brother U.S. Rep. Donald Norcross, a state senator in 2013, helped get the bill to Christie's desk.

Staff writers Mark Fazlollah, Chris Brennan, and Holly Otterbein contributed to this article.