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.

Convicted killer Gayland Bradford was executed Wednesday for the $7 robbery-slaying of a Dallas grocery store security guard almost 23 years ago.

In a final statement, Bradford, 42, thanked friends for being with him "through thick and thin."

"I am at peace," he said. "We have no worries, just as I have no more worries. To the victim's family, may you be at peace also."

As the lethal drugs took effect, he gasped a couple of times, then began snoring, each breath progressively fainter. Nine minutes later, at 6:25 p.m., he was pronounced dead.

Bradford already was on parole for a robbery conviction when he was arrested for gunning down 29-year-old Brian Williams four days after Christmas in 1988. The shooting came on Williams' second day on the job at the market a few miles south of downtown Dallas.

Williams' mother and brother were among the people in the death chamber, watching through a window just a few feet from Bradford.

"We have no anger towards Mr. Bradford and forgive him of his crime against our family," Williams' brother, Gregory, said in a statement released following the punishment. "We now turn our thoughts and prayers to Mr. Bradford's family and friends and pray that God will give them the strength, comfort and understanding as they now grieve the loss of their loved one."

The U.S. Supreme Court last week refused to reconsider an appeal they rejected earlier, clearing the way for Bradford to become the fourth Texas prisoner executed this year. Three more lethal injections are set for this month in the nation's busiest capital punishment state.