Fort Lauderdale-Hollywood International Airport remained closed Friday, after the Federal Aviation Administration issued a nationwide "ground stop" for flights traveling through Fort Lauderdale. At Philadelphia International Airport, Philadelphia police and other law enforcement agencies have increased "visible security" throughout the airport, said PHL spokeswoman Mary Flannery.

Airlines, including American, Delta, JetBlue, and Southwest, canceled all flights into Fort Lauderdale for the rest of Friday.

American canceled 3:45 p.m and 6 p.m. flights from PHL to Lauderdale. JetBlue Airways scrapped its 4:53 p.m. departure. Spirit Airlines' 5:51 p.m. flight was listed as delayed on the airport's website

American, Philadelphia's dominant carrier, said, "The thoughts and prayers of the entire American Airlines family are with the Fort Lauderdale community. The active shooter situation occured in Terminal 2; American operates out of Terminal 3. All of our employees are safe and accounted for."

Southwest, which operates in Terminal 1, said, "To our knowledge, no Southwest customers were injured."

American said two flights in the air destined for Fort Lauderdale landed safely, and two other flights were diverted to other nearby airports.

Delta Air Lines said as of 3:45 p.m. it had diverted six Fort Lauderdale-bound flights to Palm Beach, Miami, Orlando, and Jacksonville, Fla., and canceled 14 flights.

The FAA said at 3 p.m., "Flights are not arriving or departing from Ft. Lauderdale-Hollywood International Airport (FLL) at this time. Several flights have diverted to other South Florida airports. The Federal Aviation Administration has put in a ground stop for flights around the country that are destined for FLL, they are are being held on the ground at the origination airport. Travelers headed to FLL should check with their air carriers. We will update this statement when we get new information."

Delta, which operates in the baggage claim area in Terminal 2 where the shootings occured, said it has dispatched specially-trained "care team members" to Fort Lauderdale "to assist families and friends of customers and employees who may have been impacted by the shooting."

Delta said "preliminary reports" indicated all Delta employees were safe and accounted for.

Airlines issued travel waivers for customers allowing them to rebook their trips without change fees.

"We're grateful to the first responders on the scene who immediately went into action to evacuate our customers and employees," said Delta CEO Ed Bastian. "I also want to thank our employees in the operation in Fort Lauderdale and beyond who are working to re-accommodate our customers. The safety of our customers and employees is our deepest core value, and we are providing our complete support to authorities as the situation develops."

American said, "Law enforcement is reporting one suspect in custody. However, the situation continues to develop and we are working with local law enforcement as events unfold."

Southwest said it was "in process of ensuring the well-being of all Southwest employees. The airfield is closed and congestion, roadblocks, and detours have impacted vehicular traffic around/ inside the airport s well as surrounding freeways and surface streets."