Kevin Duffy, a former federal judge in the Southern District of New York who presided over the high-profile trials of organized crime figures and terrorists behind the 1993 World Trade Center bombing, died Wednesday from the coronavirus at age 87.

His son, Kevin Duffy Jr., said Judge Duffy died at Greenwich Hospital. The judge, a resident of Greenwich, Connecticut, retired from the bench in 2016 and worked alongside his son at the firm of Duffy & Staab, his son said. Memorial plans have not been set, Duffy Jr. added.

Judge P. Kevin Castel, another Southern District judge and former clerk of Judge Duffy, called it "a sad day." He said the judge had many friends and former clerks who would gather in Castel's courtroom for Duffy's birthday, which they called "The Feast of St. Kevin," though the last one, originally set for Jan. 10, was canceled because of Duffy's health issues.

"He's had some of the most important trials there are," Castel said. "Yet despite all of this, in 44 years of service to the court, many of us know that at the heart of his greatness were small acts of care and concern for others, particularly at times when they were experiencing a bad period in their life. … John Sprizzo, who was a judge of this court, once said to me that with friends like Kevin Duffy, you don't need many friends."

Duffy, a graduate of Fordham Law School, was an assistant U.S. attorney and the administrator of the New York regional office of the Securities and Exchange Commission before he was nominated to the bench by President Richard Nixon in 1972, according to an article by Judge John Keenan, his colleague on the bench.

In the 1980s, Duffy presided over major criminal cases including the five-month federal trial of several defendants implicated in the 1981 Brink's armored car robbery and shootout, in which several defendants were also tried in state court. He also oversaw a complex trial of several members of the Gambino organized crime family, which was thrown for a loop when Paul Castellano, the family's alleged leader, was shot dead outside a Manhattan steakhouse.

The judge also oversaw trials two major terrorism cases in the 1990s. He oversaw two trials related to the 1993 World Trade Center bombing, which killed six and injured more than 1,000, and another lengthy trial over the foiled Bojinka plot, a plan masterminded by Ramzi Yousef that would have entailed blowing up several flights over the Pacific Ocean.

Shawn Regan, a partner at Hunton Andrews Kurth and a former clerk of Duffy, praised the judge's friendliness and warmth.

"On the occasion of his 40th anniversary on the bench, he revealed to an audience the central element of his legendarily brutal law clerk interview process," Regan said in an email. "He said: 'It was quite simple, really. I was looking for people who I could have as my friends for the rest of my life.'"

Duffy Jr. said the social distancing precautions required by the coronavirus pandemic have complicated the grieving process. He said the judge was "as good as [fathers] get."

"He, quite frankly, was one of my best friends, if not my best friend," he said.