Transcript for Sea lion grabs girl off dock

Okay, we're back now. That incredible rescue after a sea lion grabbed a young girl who was sitting there on the pier. Dragged her underwater and ABC's gio Benitez has more. Thankfully she's okay. We can't tell you that enough. She's okay and seems to walk away unhurt but the video is frightening. How dangerous it is to feed a wild animal. It's the shocking sea lion attack caught on tape. Oh, my. Reporter: Watch again as the meal yanks her offer the dock and taking her into the murky waters before. Her quick thinking grandfather jumps into the water to rescue the girl pulling her back on to the dock to safety. Didn't look like she was able to swim. I think she was about to drown but luckily for her her family member just jumped in right away like a second after so everything was good. Reporter: The group was feeding the powerful sea lion right before the attack Saturday. You can see it eating what looks like bread crumbs right there. Just put up signs saying do not feed the sea lions. Reporter: More curious and violent and experts say it could have mission pawsible taken the girl's dress for a piece of fish. You want to go the other way. They're massive animals with temper tantrums and can be aggressive. We've seen them engage with kids before like in this 2013 vierm video showing a concerned sea lion stopping in its tracks before a young girl fell. And while attacks are rare, aggressively curious interactions with huchls have happened like this diver who had a close encounter. And this 2015 run-in with a fisherman in San Diego. This was likely a California sea lion that can weigh nearly 900 pounds swimming up to speeds of 24 miles per hour staying underwater for as long as 15 minute. That sea lion was put into a bad situation. He felt the only thing he could do was to show his aggression. Wow, experts caution people shouldn't get too close to these animals. Just respect their space to prevent attacks like this. The harbor authority said it had warning signs but now they're adding even more, but, boy, oh, boy, that grandfather went right there to help. That was scary. That video is the biggest warning sign of them all. Absolutely.

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