Updated 9:31 a.m | Rep. Robert E. Andrews, D-N.J., will resign from Congress this month to take a job with a Philadelphia law firm, a Democratic aide confirmed to CQ Roll Call.

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Andrews, an ally of Minority Leader Nancy Pelosi, is scheduled to host an 11:30 a.m. news conference in his southern New Jersey district, according to the Philadelphia Inquirer, which first reported the news . An Andrews aide declined to comment on Andrews’ plans, but confirmed that Andrews will make a statement at the news conference later this morning.  

The 12-term Democrat is currently under investigation by the House Ethics Committee , which was reportedly questioning whether the congressman used funds from his re-election campaign to pay for a trip to Scotland for his family.  

Andrews is the second member of Congress facing an ethics investigations to resign this year. Rep. Trey Radel, R-Fla., resigned earlier this year  after he pleaded guilty for cocaine possession.  

Andrews’ resignation will likely force a special election in this district, located in the Philadelphia suburbs. In the past, New Jersey officials have scheduled special elections for election-year vacancies concurrent with regularly scheduled election dates.  

New Jersey’s 1st District is a solidly Democratic seat. President Barack Obama carried the district with 66 percent in 2012.  

New Jersey sources noted that an obvious successor is state Sen. Donald Norcross. He is the brother of the state’s most powerful Democrat, southern New Jersey fundraiser George Norcross III. But at least one state Democratic source suggested a possible dark horse candidate: Camden Mayor Dana Redd.  

The news about Andrews follows a string of recent retirements among old guard Democrats. Rep. Henry A. Waxman, D-Calif. announced last week he will not seek a 21st term. Watch our video above.  

You can find a complete list of members leaving the 113th Congress at Roll Call’s Casualty List .  

Abby Livingston contributed to this report.