The agency that owned and operated the World Trade Center urged the state's top court Wednesday to reject remaining negligence claims for the 1993 bombing by terrorists who detonated a van of explosives in the public garage beneath its twin towers, killing 6 people and injuring about 1,000.

In lawsuits citing security concerns since 1984, a jury found that the Port Authority of New York and New Jersey failed as a landlord to maintain reasonably safe premises and was 68 percent at fault, blaming the terrorists for the other 32 percent. A midlevel court upheld the verdict.

In arguments Wednesday, attorney Richard Rothman said the Court of Appeals should uphold the Port Authority's claims of governmental immunity for its counter-terrorism measures against what was an unprecedented event, a foreign terrorist attack on the U.S. In court papers, he noted that the FBI building in Washington, D.C., and the New York Police Department headquarters and the United Nations building, both in Manhattan, all had unrestricted underground parking at that time against what was regarded as a relatively low-level threat.

Rothman said the 110-story towers housed offices for the governor and several state and federal agencies, and the Port Authority was doing security assessments across its network, including airports. "Treating the Port Authority as just another landlord ... is directly contrary to the statutes under which the World Trade Center was created," he said.

Even if regarded under the law as a commercial landlord, Rothman argued it was likewise undisputed that authority officials had many high-level meetings about security and were in touch with federal authorities before the bombing. The twin towers were destroyed on Sept. 11, 2001, when jetliners hijacked by terrorists flew into them.