The commissioner of Kenyan police announced today that the death last week of conservationist Joy Adamson is now believed to have been murder. Three former employes were being questioned.

Kenyan President Daniel arap Moi, a firm supporter of wildlife conservationists here, announced a full investigation into the death of Adamson, 70, who was best known for the book "Born Free" that crowned her work with lions.

Her death on Thursday at the Shaba Game Reserve, 200 miles north of here, first was attributed to a lion or leopard. But those who saw the body, discovered near Adamson's camp, said there were no claw marks and no blood to be seen.

[In Geneva, the Associated Press reported, the World Wildlife Fund's conservation director, Lee Talbot, said: "When I first heard of Joy's death, I stated that I was skeptical that a wild animal did it. Joy was so knowledgeable about wildlife that it was highly unlikely she would be killed by a wild animal."]

Police quoted a pathologist's report following an autopsy here Saturday as saying Adamson suffered puncture wounds on the side and shoulder, probably from a sword-like knife, although no weapon had been found. Police also said the Austrian-born naturalist's auto had been stolen.

There were no details on the three persons being questioned. Adamson's husband, George, a retired game warden arrived here from another reserve where he had been working. They had lived apart in recent years although they conferred frequently about their conservation efforts and research.

A close friend of the Adamsons, Ellis Monks, citing what he said was conclusive evidence that she was murdered, declared, "We are more outraged than shocked that her life ended in this manner. It is so pointless."

Monks is executive director of the World Wildlife Fund. It was Monks who said on Friday that Adamson probably was killed by a lion. He said then that Adamson's assistant, Peter Morson, a Kenyan, and three coworkers heard no sounds at the camp but found her after setting out when she failed to return from a walk.

Police offered no motive for what they now say was murder. The Adamsons were prominent members of the forces here trying to restore Kenya's wildlife, a movement which has severely threatened the livelihood of poachers and hunters.

Neighbors around the Shaba enclave quoted by United Press International said Adamson had been having trouble with her staff recently and had fired a number of employes.

Proceeds from Adamson's book and the movie and song it inspired went to the Elsa Wild Animal Fund -- named for the lioness heroine of "Born Free" -- that has provided millions of dollars for Kenya's conservation efforts.

The World Bank and several governments have provided spotter aircraft and backwoods vehicles for the Kenyan game department to wage war on poachers. The war is still far from won despite bans on hunting and curio sales.

There also is increasing concern that the tourism which the wildlife had generated is also a threat to the animals, with tour buses disturbing their habitat in pursuit of the close encounters.