The deadline expired early Thursday for illegal farmworkers seeking federal immigration amnesty, and officials said most of the late applicants in the West probably submitted fake papers, some sold by counterfeiters at $700 each.

Applicants filed through immigration offices across the country by the thousands Wednesday to meet the midnight deadline for requesting legal resident status under the government's Special Agricultural Workers Program.The biggest last-minute surge was in California, where about half of the 1.1 million applications received through last week were filed. Texas was also busy, with long lines at some locations.

Immigration and Naturalization Service offices remained open until midnight to accommodate the rush, and anyone in line by midnight was allowed to submit an application, officials said.

As of midnight PST, more than 20,000 people had filed on Wednesday in the 16 INS offices of the Los Angeles district, including about 2,500 at the biggest office, in East Los Angeles.

"We figured it would be more than that," said Neil Henry, deputy district director. "We don't know why (there were not more). We hope it was because of the pressure we put on to not file false documents. Those who qualify, we want you here, but if you don't, don't turn in false papers."

But INS officials in the West said they believed that as many as 95 percent of the applications filed in the last 45 days were accompanied by fraudulent papers, many of them obtained for a fee from professional counterfeiters.

Dozens of people accused of producing and selling bogus farmworker documents were arrested in the Los Angeles area in the past six weeks, INS district director Ernest Gustafson said.

He said many of those seeking U.S. residency by falsely claiming to be farmworkers probably were denied resident status under the government's general amnesty for all undocumented aliens that ended May 4. Both programs were established by the Immigration Reform and Control Act.

"These are a desperate group of people using desperate measures," Gustafson said.

The general amnesty provided eligibility for legal residency to all undocumented immigrants who could show they had arrived in the United States before 1982 and had lived in this country continously since then. They had a year to apply.

The agricultural amnesty program gave applicants an 18-month deadline and merely required them to submit documents showing they had been employed for at least 90 days between May 1985 and May 1986 as farmworkers.

Gustafson speculated that the relatively small amount of documentation required under the farmworker amnesty lent itself to fraud, saying, "All you need is one document alleging 90 days picking strawberries."

Harold Ezell, the INS commissioner for the West, said he believed the fraud rate for applications submitted in that region in the last 45 days was 85 percent to 95 percent. He said he expected as many as 40 percent of Western applications would be denied by the time all were processed.

Only about 3 percent of the applications processed so far under the general amnesty were rejected, INS officials said.

The Los Angeles INS district office, which covers seven counties, was receiving about 800 applications a day two months ago, with approval recommended for about 80 percent, Gustafson said.

But the daily load of applications there had increased steadily over the past five weeks, and immigration officials were finding that "about 95 percent are fraudulent," Gustafson said.