Washington ? The 9-11 terrorist attacks produced the single deadliest day in the history of U.S. law enforcement – 72 officers killed – yet almost as many died in nonterrorist incidents during 2001 as violence against police rose to a four-year high.

The collapse of the World Trade Center in New York after the twin towers were struck by hijacked airliners accounted for 71 of last year’s 142 law enforcement killings, the FBI reported Monday. The 72nd victim was a U.S. Fish and Wildlife Service officer who died when a plane commandeered by terrorists crashed in a Pennsylvania field.

Overshadowed by the enormity of those numbers is another statistic: 70 other law enforcement officers were killed by criminals around the country in 2001, the highest number since 1997 and a 37 percent increase over the 51 slain in 2000.

Still, the nonterrorism deaths are far below those recorded in the 1970s, when it was common for more than 200 officers to die violently or in accidents every year, said Craig Floyd, chairman of the National Law Enforcement Officers Memorial Fund in Washington. That number for 2001 would be about 148.

“Fewer police are being killed in the line of duty than there were 30 years ago,” Floyd said. “We’ve got more police on the street than we’ve ever had. They have better training, and they’re no longer outgunned by the criminals.”

Police are most likely to be shot to death with a handgun. All but nine of the nonterrorism murders involved a firearm.