The Federal Aviation Administration has suspended a supervisor and the controller handling the small plane that collided with a tour helicopter over the Hudson Saturday.

The FAA says it has learned the controller was involved in what it's calling inappropriate phone conversations at the time of the accident.

The agency also says a supervisor was not present in the building as required.

The FAA says it is continuing to work with National Transportation Safety Board officials in their investigation.

In a released statement Thursday, the agency said, "While we have no reason to believe at this time that these actions contributed to the accident, this kind of conduct is unacceptable and we have placed the employees on administrative leave and have begun disciplinary proceedings."

The FAA says it is putting together a group of safety and air traffic experts to consider whether some recommended safety measures for the Hudson corridor should be required.

The agency sent out a reminder to pilots flying through the corridor to follow those recommended safety measures, including tuning into a radio frequency where they can communicate with each other, flying at speeds less than 140 knots and turning on their lights.

The group will review the current measures and determine whether changes should be made.

Nine people were killed when a sightseeing helicopter and a small plane collided over the Hudson River Saturday.