Federal officials now say the six sea lions found dead in traps near Bonneville Dam apparently were not shot to death, leaving open the questions of how the animals died or whether humans killed them.

NOAA Fisheries officials say preliminary results of a necropsy found no evidence of recent gunshot wounds but found numerous shallow puncture wounds in one animal consistent with sea lion bite marks.

The department still is trying to determine how the animals died and how the doors to the traps in which they were found had been closed.

Investigators had believed the animals were shot at close range with high-powered rifles, the bullets passing through the flesh.

X-rays found metal fragments in soft tissue near the neck of two animals, and a metal slug was found in the blubber of one animal. However, neither the fragments nor the slug appear to be fatal and may have been from old wounds.

The Humane Society, which is suing to block the authorized killing or removal of up to 85 animals a year for five years, agreed with the federal government and the states of Oregon and Washington to continue a ban on killing and stop permanent removal until next year, in part to allow more efforts to go toward investigating what was thought to be shootings of the animals over the weekend. The agreement allowed the governments to continue removing animals and branding them for identification if they return them to their natural habitat.

(AP)