New York ? Opening the door to scores of Sept. 11 lawsuits against the aviation industry, a judge concluded Tuesday that the hijacking and crashing of a jetliner was a “foreseeable risk.”

U.S. District Judge Alvin Hellerstein said negligent security screening might have contributed to the deaths of 3,000 people in the attacks on the World Trade Center and the Pentagon, and the crash of a hijacked plane in Pennsylvania.

“The aviation defendants controlled who came onto the planes and what was carried aboard. They had the obligation to take reasonable care in screening,” he wrote.

Hellerstein cautioned that, early in the legal process, he viewed evidence in a light most favorable to the plaintiffs — over the objections of defendants American and United airlines, the Boeing Co. and the Port Authority of New York and New Jersey.

The decision involved the cases of about 70 people injured or killed in the attacks.

As a result of the ruling, court officials were preparing for a possible rush of lawsuits as early as this week as some people choose litigation over the federal victims compensation fund. To receive a payout from the fund, families must agree not to sue airlines or other entities.

American Airlines spokesman Todd Burke said the airline would appeal. “We continue to believe that we are not liable for the events that occurred that day,” he said.

Port Authority spokesman Steve Coleman said the agency strongly believed “the responsibility rests with the murderers who led the attacks.”

Boeing spokesman Ken Mercer said the jet manufacturer also would appeal. “Terrorism, not negligence, is the issue at hand here.”