The Federal Aviation Administration is cracking down on safety protocols, citing “six serious runway incursions” that occurred since January.

These incidents were discussed at a safety summit on March 15, a meeting that followed a “call to action” issued by the acting FAA administrator, “to ensure focus and attention on risks to the aviation system.”

“In recent months, a number of notable and high visibility events have occurred in the National Airspace System,” stated the FAA alert issued on Wednesday.

“While the overall numbers do not reflect an increase in incidents and occurrences, the potential severity of these events is concerning.”

According to the alert, six serious runway incursions have occurred since January, including an incident at John F. Kennedy International Airport in New York City, “involving a taxiing aircraft narrowly avoiding a departing aircraft.”

The FAA also cited a landing aircraft that came within 100 feet of a departing aircraft” at Austin-Bergstrom International Airport in Texas.

Earlier this month in Massachusetts, U.S. Rep. Stephen Lynch called for a review of FAA flight operations and an update on investigations into three recent “troubling” incidents at Boston Logan International Airport.

On March 6, the right wing of a United Airlines plane struck the tail of another United plane, as both were set for departure. A week earlier, a JetBlue plane preparing to land had a “close call” with a Learjet aircraft.

The latter incident occurred a day after a Massachusetts man allegedly attacked a flight attendant and tried to open an emergency exit door on a United flight headed to Boston.

The FAA’s safety alert outlines specific steps it wants airlines, pilots and others to take. This includes ensuring pilots and flight attendants have the same understanding of what “sterile flight deck” means and the risks associated with extraneous communication during this time.

The FAA is also emphasizing the importance of aircraft awareness in relation to taxiways, runways and other aircraft.

This includes reviewing past safety alerts for operators around high collision risk during runway crossing, runway incursion prevention actions, and flight crew techniques and procedures to enhance taxi, pre-takeoff, and after landing safety to reduce the risk of runway incursions.

Other directives are focused on encouraging staff to identify and report emerging safety issues, reinforcing adherence to FAA processes and procedures, and ensuring safety management systems are accounting for the high rate of change and churn in the industry.