Was it a terrorist intent on destroying an airplane? Or was it a passenger armed only with battery-powered "massage shoes" to comfort aching feet, who found himself cooling his heels in jail?
On Tuesday, amused airport security officials in the southwestern Pakistani city of Karachi played down a major terrorism alert from the previous evening, when the arrest of a passenger prompted warnings that the country's first "shoe bomber" was in custody.
"It was all just a hype," a Karachi-based Pakistani intelligence official told CBS News on condition of anonymity. He explained that the passenger had shoes designed to massage one's feet. "There are wires and battery cells inside, connected to strips meant to massage," the official said.
"These days, everyone is very nervous. This arrest immediately prompted a scare. No explosives were found but the story about the massage shoes looks plausible," added the official, who said they had never seen such a thing before.
Around the world, security at airports was tightened to include shoe searches after Richard Reid, a British Islamist militant, tried to blow up an airliner over the Atlantic in 2001 using explosives hidden in his shoes.
The "Shoe Bomber" case unleashed a number of high profile and embarrassing events where even top national leaders have not been spared from having to take off their shoes during security screenings.
The passenger, Faiz Mohammad, was arrested in Karachi on Monday before he could board a Thai Airways flight to Muscat, the capital of the Persian Gulf sultanate of Oman. He told investigators that he had bought his shoes at a store in Karachi and wore them to comfort his feet during the hour-long flight.
On Tuesday, a team of Pakistani police and intelligence officials visited the store in Karachi's Saddar shopping district to verify the claim.
"We are trying to establish if there are other shoes like Faiz Mohammad's shoes to verify his story," said a Karachi police officer who also spoke to CBS News on condition of anonymity because he was not authorized to speak to journalists.
He declined to say if the police had, in fact, found similar pairs of shoes. But media reports described them as the Good Vibrations Therapeutic Vibrating Shoes ®, which sport two-tone colors, and come with a battery recharger and handy on-off switch.
Though Pakistani officials were eventually treating the case as a harmless event with little apparent relevance to global terrorism, the case comes during a week of heightened alert following the failed attempt to bomb New York's Times Square on May 1.
The arrest of Faisal Shahzad, the U.S. national of Pakistani origin, in connection with the failed attempt in New York has renewed anxieties over Pakistan's links to global terrorism.
American investigators interrogating Shahzad are believed to have established his contacts with Taliban militants from Pakistan's region along the Afghan border, in yet another reminder of the threat to Western countries that emanates directly from Islamic militants operating in Pakistan and Afghanistan.
By CBS News' Farhan Bokhari reporting from Islamabad