One man was killed and two people were injured in a grizzly bear attack at a campground close to Yellowstone National Park, dpa quoted wildlife and law enforcement officials as saying Thursday. The attack happened overnight Wednesday and the bear was caught with three of her cubs when she returned to the scene of the attack, according to wildlife officials. The aggressive mother bear is to be killed, but the fate of the cubs is yet to be decided. The Missoulian newspaper reported that the man who was killed was camping on his own away from the main campsite. The bear then went on the rampage through the site, tearing through tent walls to get at occupants. One of the victims told the paper that she played dead to get the bear to leave her alone. Deb Freele of London, Ontario, said she woke up just before the bear bit her arm. "I screamed, he bit harder, I screamed harder, he continued to bite," she said. "I told myself, play dead. I went totally limp. As soon as I went limp, I could feel his jaws get loose and then he let me go." Officials said the attack was the worst in the area since 1980. Bear attacks usually occur when the animal feels it or its cubs are threatened but this attack appeared to be unprovoked. "This, to me, was just an absolutely freaky thing," said Freele. "I have to believe that the bear was not normal. It was very quiet, it never made any noise. I felt like it was hunting me."