The New York helicopter tour company that operated the sightseeing tour that crashed into the Hudson River last week, killing all six aboard, has been grounded by the Federal Aviation Administration, the agency said Monday.

The FAA said the emergency order to ground New York Helicopter Charter, Inc., was due in part because the company’s director of operations had been fired.

The Bell 206 helicopter crashed into the Hudson River at 3:17 p.m. Thursday, officials said.

Siemens executive Agustín Escobar, his wife, Merce Camprubi Montal, their three children and pilot Sean Johnson were killed.

New York Helicopter Charter had voluntarily shut down flights after the crash, the FAA said.

The cause of the investigation is ongoing.

The FAA is also conducting a review of the company’s operations, known as a Certificate Holder Evaluation Program, the aviation agency said.