An American Airlines flight from Washington, D.C. landed safely at Logan International Airport Wednesday after the crew reported a hydraulic issue, authorities said.

Flight 2120, an Airbus 319, took off from Ronald Reagan National Airport and landed in Boston at 5:49 p.m. “after the crew declared an emergency,” the Federal Aviation Administration said in a statement.

The agency is investigating, the statement said.

American Airlines said in an e-mail that the flight crew reported “an indication of a possible issue” and that the plane landed safely.

Adam Sennott can be reached at adam.sennott@globe.com.