The 911 calls began shortly before 8 a.m. Tuesday.

Callers reported that two hot air balloons were drifting directly over rooftops and into trees in Yucapia, California, southeast of San Bernardino, according to the San Bernardino County Sheriff’s Department. Deputies spotted the balloons, one green and one blue, passing within a few feet of rooftops.

“Deputies were able to make contact with both pilots, and requested them to land immediately,” read a press release from the sheriff’s office. One balloon landed in a high school baseball field while the other touched down in a grove of orange trees at a private home.

The pilots were both flying their privately owned balloons for fun, deputies reported. Authorities will forward a report on the incident to the Federal Aviation Administration. There were no reports of injury or damage.

FAA regulations on aircraft, including hot air balloons, require pilots to stay 1,000 feet or more above the highest obstacle when flying over congested areas of cities or towns, except when landing or taking off. They’re required to stay 500 feet or more above the ground in unpopulated or lightly settled areas.

A Balloon Flying Handbook issued by the FAA in 2008 notes that some balloonists are unaware that they’re expected to follow the same altitude rules as airplanes or other aircraft.

There are about 10,000 licensed balloon pilots worldwide, and about 5,000 in the United States, according to Balloon Safaris International.