Police have released the chilling 911 calls detailing the moment the helicopter carrying Kobe Bryant and eight others crashed into the ground, killing everyone on board.

The helicopter, flying through heavy fog, plunged into the Calabasas hills just over a week ago.

Now, police have released the harrowing calls witnesses made to authorities, with many reporting seeing the aircraft crash into the hills.

One caller said he was walking on a trail when he heard the helicopter go down above him.

"I'm walking in the trail, I could hear the plane, I think it was, in the clouds, but I couldn't see it. Then we just heard a 'boom' and a dead sound and then I could see the flames"

Another caller described the unfavourable conditions the helicopter was flying in followed by the deafening noise of Bryant's Sikorsky S-76 chopper coming down.

"I just heard a helicopter go over me ... It went over my head. It's thick in clouds, and then I heard a pop and it immediately stopped. If the guy doesn't have night vision, I mean, he was, he's completely IFR [Instrument Flight Rules]."

One caller, at a nearby supermarket in Agoura Hills, reported to the dispatchers that a "helicopter crashed into a mountain".

"We heard it, and I'm now looking at the flames," the man, who was about a 400m away from the crash site, said.

"Helicopter crashed into a mountain. We heard it. And now I'm looking at the flames," another added.

One caller has since opened up about the horror crash, telling ABC News the visibility was poor, with thick fog making it almost impossible to see ahead.

"Imagine jumping into a pool filled with milk and opening your eyes."

BODIES RETURN TO FAMILIES

The bodies of Kobe Bryant and his 13-year-old daughter, Gianna, have been released to their family by the Coroner a week after their helicopter fatally crashed.

Their remains were returned after confirmation of their identity and a cause of death was determined by investigators.

The remains of the pilot, Ara Zobayan, and passengers Christina Mauser, 38, Sarah Chester, 45, and her 13-year-old daughter Payton, have also been released, a spokeswoman confirmed.

Passengers John Altobelli, 56, his wife Keri, 46, and their daughter Alyssa, 14, are ready to be released, but have not yet been picked up by family members, according to the coroner's office.

Just days after the tragedy, Bryant's wife broke her silence, sharing a heartbreaking tribute for her husband and daughter.

Along with the tribute, Vanessa Bryant, the widow of late NBA legend, shared a photo of their family.

"My girls and I want to thank the millions of people who've shown support and love during this horrific time. Thank you for all the prayers. We definitely need them. We are completely devastated by the sudden loss of my adoring husband, Kobe — the amazing father of our children; and my beautiful, sweet Gianna — a loving, thoughtful, and wonderful daughter, and amazing sister to Natalia, Bianka, and Capri," she wrote.

"We are also devastated for the families who lost their loved ones on Sunday, and we share in their grief intimately.

"There aren't enough words to describe our pain right now. I take comfort in knowing that Kobe and Gigi both knew that they were so deeply loved. We were so incredibly blessed to have them in our lives. I wish they were here with us forever. They were our beautiful blessings taken from us too soon.

"I'm not sure what our lives hold beyond today, and it's impossible to imagine life without them. But we wake up each day, trying to keep pushing because Kobe, and our baby girl, Gigi, are shining on us to light the way. Our love for them is endless — and that's to say, immeasurable. I just wish I could hug them, kiss them and bless them. Have them here with us, forever.

"Thank you for sharing your joy, your grief and your support with us. We ask that you grant us the respect and privacy we will need to navigate this new reality.

"To honour our Team Mamba family, the Mamba Sports Foundation has set up the MambaOnThree Fund to help support the other families affected by this tragedy. To donate, please go to MambaOnThree.org.

"To further Kobe and Gianna's legacy in youth sports, please visit MambaSportsFoundation.org.

"Thank you so much for lifting us up in your prayers, and for loving Kobe, Gigi, Natalia, Bianka, Capri and me. #Mamba #Mambacita #GirlsDad #DaddysGirls #Family "