The U.S. military is flying surveillance drones over the Gaza Strip, according to two Defense Department officials and an analysis by The New York Times. The officials said the drones were being used to aid in hostage recovery efforts, indicating that the U.S. is more involved than previously known.

The aircraft are MQ-9 Reapers operated by U.S. Special Operations forces and were first spotted on Saturday on Flightradar24, a publicly accessible flight-tracking website, though Pentagon officials said that the aircraft have been active in the area since the days after the Oct. 7 surprise attack on Israel by Hamas.

While Israel frequently conducts reconnaissance flights over Gaza, U.S. defense officials said it was believed to be the first time that U.S. drones have flown missions over Gaza.

The flights are operating at a critical juncture. Israel is in the early stages of a ground invasion in Gaza and says Hamas is holding more than 240 hostages, 10 of whom are believed to be Americans.

The unarmed surveillance flights are not supporting Israeli military operations on the ground, according to the Defense Department officials. Two officials said the goal was to assist in locating hostages, monitor for signs of life and pass potential leads to the Israel Defense Forces.

The U.S. military has been providing military aid, including bombs and artillery rounds, to Israel, and has deployed two aircraft carriers and hundreds of troops to the Middle East since the Oct. 7 attack. Several dozen American commandos have been dispatched to Israel to help advise on hostage recovery efforts. But the surveillance flights suggest that the Pentagon is taking a more active role in a key I.D.F. mission to rescue hostages.

The flights are concentrated in southern Gaza, approximately 15 miles from the Israeli military’s initial push in the north. There appear to be at least six separate MQ-9 aircraft involved in the effort, according to Amelia Smith, an aviation researcher who has been tracking the flights. Several aircraft analyzed by The Times and Ms. Smith loitered over Gaza for about three hours, at 24,000 to 26,000 feet.

The MQ-9 was designed as the U.S. Air Force’s first “hunter-killer” drone, but it is primarily used for surveillance missions because of its sophisticated sensors and ability to loiter above an area for more than 20 hours at a time. It has been used to conduct airstrikes and collect intelligence in Iraq, Afghanistan and Syria. The MQ-9 is used by many militaries around the world, but not by Israel.