The Federal Aviation Administration is investigating a narrowly missed midair collision between a United flight and a Delta flight at Phoenix Sky Harbor International Airport on Saturday, the agency said.

The United and Delta flights were less than a quarter of a mile apart horizontally before the warning devices went off, officials say.

The pilots talked to air traffic controllers who appear to have directed the planes to "resequence," and flight data appears to show both making a circle before landing safely.

The close call between the United and Delta flights at the Phoenix airport comes amid an increase in plane near-collisions.

The Federal Aviation Administration is once again looking into a close call at a major U.S. airport, after two passenger jets narrowly avoided a mid-air collision as they attempted to land in Phoenix.

A United flight from San Francisco and a Delta flight from Detroit came within 425 feet of each other in the sky, according to flight radar data. NTSB guidelines say planes should always stay at least five miles apart.

The Federal Aviation Administration (FAA) said it is investigating a recent near-midair collision of flights that were approaching Phoenix Sky Harbor International Airport. A Delta Air Lines

The FAA has launched an investigation into a loss of separation between two commercial flights in Phoenix Saturday.

The two flights, United Airlines Flight 1724 and Delta Air Lines Flight 1070 came too close to each other while arriving at the airport.

FAA officials say the two planes "landed safely after experiencing a loss of required separation" as they were headed to Sky Harbor.

The Federal Aviation Administration (FAA) is investigating after a United ... had a near-collision while preparing to land in Phoenix over the weekend. United Airlines Flight 1724 and Delta ...

The Federal Aviation Administration is investigating after a United Airlines flight and a Delta Airlines flight had a near-collision over Phoenix on Saturday.