A Fremont police officer confirmed the gator sighting and officials began the search for it after a man reported it Monday afternoon.
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California Fish and Wildlife game wardens said they decided that euthanizing the animal, by shooting it in the head, was the best option.
From Sky 7HD you can see one of the men sent in to find the gator holding a covered cage walking out of the creek.
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The alligator was put in that cage after it was shot. "Our department issued a 308 rifle, and he was shot in the head, so he died immediately," US Department of Fish and Wildlife Warden Capt. Sheree Christensen said.
Game wardens said the American alligator was on a rock sunning when they arrived.
"It's inhumane basically, I mean we have the resources, we have all these people down here to take care of it, I think they're just taking the easy way out, instead of catching it," neighbor Sam Cuellar said.
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Game wardens opted to shoot the alligator because they say it posed a safety risk for people, pets and other animals in the area.
"It's very, very difficult to tranquilize an alligator from a distance. And they're very spooky around people, so if we tried to get close to it we would lose it and we didn't want to take that chance," Christensen said.
It's not clear how long the alligator was in the creek. One local said he spotted it months ago. "I saw it on a rock when I was hanging out with some buddies back here and he scared it off by making some loud noises because he was too excited. It swam into the water before I could get a picture of it," Steven said.
Steven said that incident occurred six months ago.
California game wardens figure someone left the animal there after it became too difficult to keep as a pet. They say they could've worked with the owner to ship it to a different state instead of having to kill it in the wild.
CA Fish & Wildlife and Fremont Police officers have located and captured a 4 Foot alligator in Alameda Creek. pic.twitter.com/52AyeqoVTO— Sergio Quintana (@svqjournalist) August 16, 2016
Alligator update: US Fish and Wildlife are on-scene and have located the animal. They are handling all media inquiries.— Fremont Police Dept (@FremontPD) August 16, 2016