Despite an airline strike and stepped up enforcement, immigration agents arrested 40 more illegal aliens at Los Angeles International Airport in a crackdown on the smuggling of immigrants aboard airliners, authorities said Saturday.

The roundup late Friday and early Saturday was the sixth this week, bringing the nationwide arrest total to 286.Three of those taken into custody were alien smugglers, or "coyotes," alleged organizers of the operation who are paid to smuggle Mexican and Central American immigrants into the United States through Southern California then onto flights to the Midwest and Eastern cities, said Immigration and Naturalization Service spokeman John Brechtel.

The coyotes were to be arraigned Monday in U.S. District Court on charges of alien smuggling, Brechtel said. Their names were not immediately available.

The majority of those arrested at the airport between 8 p.m. Friday and 1:30 a.m. Saturday were from Mexico, he said. A breakdown of nationalities, however, was not immediately available.

Agents made the arrests at three domestic terminals, stopping aliens from boarding flights to Chicago, Atlanta, Dallas and New York, including Eastern's Flight 80, the same Los Angeles-New York flight first targeted by the INS when the crackdown began Monday.

The flight had been scheduled to depart minutes before the strike by Eastern workers began at midnight. It was canceled.

Agents also seized two cars believed to belong to two of the coyotes, Brechtel said.

Aside from the smugglers, the balance of those arrested were held at an INS detention facility in Los Angeles and face deportation.

Another INS raid at the airport was expected Saturday night, Brechtel said.

The investigation into the transporting of illegal immigrants through the airport has expanded to include surveillance of several "drop houses" where outbound immigrants are apparently piling up as their smugglers scramble for alternatives to deliver them to their destinations.

INS District Director Ernest Gustafson said the stepped-up enforcement at the airport has led smugglers to slow down their operations and "test the waters" with small groups of aliens, who he referred to as "sacrificial lambs."

Gustafson estimated that at any given time there are between 30 and 40 drop houses in the Los Angeles area.

In North Carolina, meanshile authorities said they may file smuggling charges against one of 27 illegal aliens arrested aboard a Piedmont jet last week.

The government has issued an alert to all major airlines to watch large groups of travelers with pre-purchased tickets and no luggage.