Defense Secretary Caspar Weinberger yesterday halted plans at the nation's military medical school in Bethesda to shoot dogs with high-powered weapons so surgeons and scientists could study their wounds.

Reacting to protests from Congress and animal welfare advocates, the Pentagon released a one-sentence statement saying the secretary "has directed that no dogs be shot for medical experimentation or training."

The statement left open questions of whether Weinberger would allow the medical school's new firing range to open and whether he would permit the wounding of other animals for research.

Rep. Tom Lantos (D-Calif.), who began circulating a letter on Capitol Hill Monday protesting the shootings as a "shocking waste of animal lives and tax monies," said he would continue the fight until he got a "fuller response" from the Pentagon. "The secretary's statement clearly calls for amplification," Lantos said. "Does it cover all animals, all facilities and an indefinite period of time?"

At least four other military laboratories in the nation have conducted wound research on animals in the past, according to Col. Richard Simmonds, a veterinarian at the Uniformed Services University of the Health Sciences (USUHS), where the new firing range is located. Research is still going on, using anesthetized pigs, at the Letterman Army Institute of Research in San Francisco, according to Col. Thomas Zuck, Letterman's commander.

Alex Pacheco, head of the Washington-based People for the Ethical Treatment of Animals, sought help from Lantos after he learned that the military medical school in Bethesda was building a firing range where similar research would be done.

Sponsors of the officially named "Wound Laboratory" in Bethesda, which cost about $70,000 to construct, said they need the laboratory to train aspiring doctors for battlefield medicine and to research better ways to treat combat wounds. Simmonds, the veterinarian in charge of the university's animals, said the wound research and training is both legitimate and indispensable at the school, which turns out about 150 military doctors each year.

Weinberger read of the project in the newspaper yesterday and immediately decided he would not allow it, according to military assistant Michael Burch.

Meanwhile, calls of protest poured in to the offices of Lantos and other members of Congress, to the university and the Defense Department, according to several spokesmen. One Washington radio station broadcast the telephone number of Weinberger's office and receptionists there were inundated with calls, according to one staffer.

The project called for the shooting of as many as 80 dogs a year in a 50-foot firing range, according to Simmonds. The dogs, most of them medium-sized mongrels, would be purchased for $80 to $130 each from dealers, who buy dogs from animal shelters where they are scheduled to be put to sleep, he said.

Simmonds said the dogs would be anesthetized, then shot while suspended in nylon mesh slings. Surgeons and medical students would treat the wounds, and then the dogs would be killed.