From AP, Dec. 17:

SAN DIEGO — Border Patrol agents are firing tear gas and powerful pepper-spray weapons across the border into Mexico to repel what the agency says are an increasing number of attacks by assailants hurling stones, bottles and bricks.

The counteroffensive has drawn complaints that innocent families are being caught in the cross-fire.

Esther Arias Medina, 41, fled her shanty in Tijuana with her 3-week-old grandson last week in the midst of an attack. The boy had begun coughing, Ms. Arias said, after smoke seeped through the walls of the three-room home, which she shares with six others.

"We don't deserve this," she said. "The people who live here don't throw rocks. Those are people who come from the outside. But we're paying the price."

Witnesses in Ms. Arias's neighborhood described eight attacks since August that involved tear gas or pepper spray, some that forced residents to evacuate.

The Border Patrol said its agents had been attacked nearly 1,000 times during a one-year period. The agency’s top official in San Diego, Mike Fisher, said agents were taking action because the Mexican authorities had been slow to respond. When an attack occurs, Mr. Fisher said, the agents often wait hours for Mexican officers, who, he said, usually never arrive.

"We have been taking steps to ensure that our agents are safe," he said.

In October, agents in California and Arizona received compressed-air guns that shoot pepper-spray canisters more than 200 feet. (Agents already had less powerful launchers, which lose their punch after about 30 feet.) Border Patrol SWAT teams along the 1,952-mile border are also equipped with tear gas, "flash bombs" that emit blinding light and "sting ball" grenades that disperse hundreds of tiny rubber pellets.

United States officials say the new tactics may spare lives. In March, an agent shot and killed a 20-year-old Mexican man whose arm was cocked; that fatality occurred in Calexico, Calif., where attacks with stones have soared. And two years ago, an agent fatally shot a stone thrower at the San Diego-Tijuana border.

Mexico's acting consul general in San Diego, Ricardo Pineda Albarrán, has insisted that United States authorities stop firing onto Mexican soil. Mr. Pineda met with Border Patrol officials last month after the agency fired tear gas into Mexico. The agency defended that action, saying agents were being hit with a hail of ball bearings from slingshots in Mexico.

United States officials say the violence indicates that smugglers are growing more desperate as increased security makes it harder to sneak across the border. The assailants try to distract agents long enough to let people dash into the United States.

The leader of a union representing Border Patrol employees said the violence also resulted from a decision to put agents right up against the border, a departure from the early 1990s, when they waited farther back to make arrests.

"When you get that close to the fence, your agents are sitting ducks," said T. J. Bonner, president of the union, the National Border Patrol Council.

Border Patrol agents were attacked 987 times along the border during the 12-month period that ended Sept. 30, the agency said. That was up 31 percent over the previous year and was the highest number since the agency began recording attacks in the late 1990s.

Agent Joseph Ralph estimates that he has been struck by stones 20 times since joining the Border Patrol in 1987, once fracturing a shoulder blade. "You find yourself trying to take cover," he said.

About four months ago, a large stone struck the hood of Agent Ellery Taylor’s vehicle. "The only thing you can think is, 'I'm glad that that wasn’t my head,'" Agent Taylor said. "There's no way to see it coming."

On the Mexican side, Benito Arias said his 19-year-old sister-in-law fainted during an apparent tear gas attack about two weeks ago. The woman, five months pregnant, was given oxygen at the hospital.

Mr. Arias's father, José Arias, said he sympathized with the Border Patrol because the Mexican authorities did nothing to prevent people from hurling stones over the fence at agents.

"This is a matter between government and government," the elder Mr. Arias said. "They have to work out an agreement. We are innocent. What can we do about it?"