Sources Reveal What Caused Kobe Bryant’s Fatal Helicopter Crash

There are new details surrounding Kobe Bryant's fatal helicopter crash.

Law enforcement sources tell TMZ that weather was probably to blame.

In fact, LAPD air support was reportedly grounded because of fog on Sunday.

Meanwhile, flight tracker data revealed that the chopper, carrying Kobe, his daughter Gianna, and seven others, circled the L.A. Zoo in Burbank six times at low altitude. The pilot may have been waiting for the fog to clear.

The pilot did reach out to the Burbank Airport control tower around 9:30 a.m. Those in the tower were aware the helicopter was circling the area for about 15 minutes.

Eventually, the craft headed north along the 118 freeway and then west along the 101. At 9:40 a.m. the pilot turned south in a mountainous region. TMZ reports that the helicopter suddenly climbed from 1,200 feet to 2,000.

Minutes later, flying at 161 knots, the chopper crashed into a mountain near Calabasas. They were flying at about 1,700 feet at the time. There were no survivors.

“Extra's” Samantha Harris was on location in Calabasas just after the accident.

Harris spoke to Scott Daehlin, who was outside a nearby church just before the chopper went down. He described the chopper hovering directly above him before moving off and crashing.

Jerry Kocharian was also outside the church, and told Harris he heard the crash and saw smoke and fire in the distance.

The investigation is now in the hands of the National Transportation Safety Board and Federal Aviation Administration.

Kobe and Gianna were en route to the Mamba Academy in Thousand Oaks for basketball practice, according to TMZ.

They are survived by wife and mom Vanessa, and by his children with Vanessa, Gianna's sisters Natalia, 17; Bianka, 3; and Capri, 7 mos.

Watch "Extra's" past interviews with Kobe below.