Mice carrying a dangerous disease were among 1,231 research animals stolen, a University of Arizona researcher said in the wake of Monday's arson fires for which an activist group also claimed credit.

A group identifying itself as the Animal Liberation Front claimed responsibility for the "liberation" of mice, rabbits, guinea pigs, frogs and rats and for two early-morning arson fires that caused an estimated $100,000 damage.Michael Cusanovich, university vice president for research, said the vandalism and thefts amounted to terrorism and "a direct attack on the health and welfare of the people of this country."

He said, "The animal research carried out by our investigators contributes in a major way to alleviation of suffering and the prevention and the cure of illness of the people of Arizona and around the world."

Charles Sterling, a veterinary sciences professor, said 30 mice about a week old were infected with the parasite cryptosporidium, which causes what he called a Third World disease affecting the gastrointestinal tract of humans and many animals.

The mice were in a locked room with warning signs posted, he said.

John Mulder, director of animal care resources, said 1,160 mice, 42 rats, 16 rabbits, nine guinea pigs and four frogs were taken.