WASHINGTON (Reuters) -The Federal Aviation Administration on Tuesday issued a safety alert to airlines over risks from lithium batteries in aircraft passenger compartments, citing a large number of serious incidents.

The FAA recommended airlines adopt risk mitigation strategies including clear messaging to address potential fire risks tied to lithium batteries carried by passengers and crew members and review firefighting procedures and training.

There have been 50 U.S.-reported lithium ion battery smoke, fire or extreme heat incidents reported this year, the FAA said.