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. Last Updated: 07/27/2016

Unabomber Note Valid, but a 'Prank'

LOS ANGELES -- After throwing air travel and mail delivery into chaos with a threat to blow up a plane out of Los Angeles, the "Unabomber," the elusive U.S. parcel-bomber, said it was all just "one last prank.''

The New York Times said late Wednesday it had received a letter in which the Unabomber took responsibility for the bomb threat and said the whole thing was a ruse.

"Since the public has a short memory, we decided to play one last prank to remind them who we are,'' the letter said. "But, no, we haven't tried to plant a bomb on an airline -- recently.''

The letter also expressed remorse for some past acts.

"We don't think it is necessary for us to do any public soul-searching in this letter. But we will say that we are not insensitive to the pain caused by our bombings.''

The Times said the FBI authenticated the mail late Wednesday, but said the agency would continue to take the threat seriously.

The threat to blow up a plane by the July Fourth holiday weekend temporarily grounded all mail in California on Wednesday and imposed the tightest airport security since the Gulf War.

The warning received Tuesday by the San Francisco Chronicle, read: "WARNING. The terrorist group FC, called unabomber by the FBI, is planning to blow up an airliner out of Los Angeles International Airport some time during the next six days.''

It represented the first time the mysterious bomber had threatened a target in advance.

The typewritten letter was pronounced authentic by the FBI.

"We are taking it very seriously ... We do deem it to be a credible threat,'' said Ed Jones, division manager of security for the Federal Aviation Administration.

FBI agent Jim Freeman said he is "100 percent'' sure the letter is from the Unabomber, the name the FBI has given the person who has killed three people and injured 23 with 16 package bombs since 1978.

At airports from San Francisco to Los Angeles and San Diego, passengers had to produce photo ID at counters and curbside baggage check-ins and were told their bags might be opened. The FAA also warned travelers to watch out for suspicious bags or parcels and to expect security delays.

Long lines formed as ticket agents checked passengers' identification.

"I feel unsafe, but I try not to let it ruin my life,'' said John Mulcrone of West Hollywood, who had to produce his driver's license as he checked in at the curb at Los Angeles International.

But others took precautions.

Tracy Woods, originally scheduled to fly to Dallas from Los Angeles International Airport, switched to a flight out of Burbank Airport.

"I do ... take this fellow really seriously, somebody who has been able to elude the FBI for this long,'' she said.

At the airport, which is the world's fifth busiest, handling nearly 1 million passengers a week, police added officers and posted one with a bomb-sniffing dog near the United shuttle gate. A United Airlines president was once the target of the Unabomber.

Some airlines waived fees for passengers wanting to change their flights. All mail flown in and from California was ordered halted for most of the day. Many of the Unabomber's explosives have been mailed from Northern California post offices, and the FBI has said the bomber probably lives near Sacramento.

Late Wednesday, the Postal Service said it had worked out guidelines with the Federal Aviation Administration to resume shipment of letters. It said it also would soon resume package service under heightened security measures.

In Sydney, Australia, police searched a United Airlines jet that arrived from Chicago and Los Angeles on Thursday morning after a bomb scare.

Passengers said that about two hours from Sydney the crew told them it suspected a bomb was in the rear of the plane. The passengers were herded toward the front of the 747 until it landed.

A police source, speaking on condition of anonymity, said the device was not a bomb.

The most recent victim of the Unabomber, so-named because many of his bombs were aimed at universities and airlines, was timber industry lobbyist Gilbert Murray, killed in his Sacramento office April 24.