It was seven minutes into Mass last Sunday when FBI supervisory special agent Edward M. Quinn's beeper went off.
He never got to hear the sermon.
Instead, Quinn, the head of the FBI's Reactive Squad in Boston, rushed to the scene of a startling robbery at the Isabella Stewart Gardner Museum -- where two men, reportedly disguised as police officers, overpowered guards and stole an estimated $200 million worth of the museum's most precious paintings.
By the time collection plates were being passed around in Boston's churches, Quinn, Thomas Hughes, the special agent in charge of the FBI in Boston, a team of FBI agents and Boston police had launched an investigation into the theft.
As Sunday suppers were being set on the table, federal and local authorities had secured the museum, taken photographs, dusted for fingerprints, started working up a list of suspects, and had alerted Interpol, the international police agency, to the crime.
And by early Monday morning, FBI teletypes started clicking around the world with a complete description of the art objects, including paintings by Vermeer and Rembrandt, that had been stolen.
So began the work of federal and local crime bloodhounds, sniffing along the trail of what could be the nation's biggest art heist.
While the FBI would not release details of its probe yesterday, interviews with FBI officials and other law enforcement authoritiews revealed a general outline of how such investigations are conducted.
Of primary importance, officials said, is securing the scene of the robbery and obtaining any clue, no matter how small, that robbers may have left behind.
Experts say that despite a professional robber's cleverness or care, he or she can leave a million telltale clues behind. Hair. Footprints. Fingerprints. Even a scrap of cloth or a cigarette butt can lead investigators to a suspect.
"A great deal of time was spent by agents strictly on the crime scene," said Quinn. "Everything taken by the FBI was sorted for a number of laboratory exams and all latent fingerprints were sent to the lab."
Investigators secured the museum for the entire day Sunday, while photographs were taken and dusting done for fingerprints, authorities said. Then, any item that may have been touched by the thieves was identified and tagged for testing in FBI labs in Washington, authorities said.
The FBI would not reveal further details. But in a typical investigation, according to Lt. George MacDougall of the Massachusetts State Police fingerprint section, even chemists may be called to the scene of a crime.
Using special equipment, he said, investigators can obtain not only fingerprints, but also footprints left behind on something even as firm as a wooden floor. And footprints can be revealing: "Every person has a way of wearing a shoe," MacDougall said.
Even if fingerprints aren't visible to the eye, they can be retrieved by specialists through a number of methods, MacDougall said. Lasers can be used to illuminate the moisture left by a fingerprint on a surface. So too, a substance known as cyanoacrylate can be used. It reacts with the amino acids left by the human touch to reveal a fingerprint, he said.
Items seized from the Gardner Museum by FBI agents are currently en route to the FBI's lab in Washington, where tests like these may be used. Law enforcement specialists consider the FBI the premier agency in the country for this kind of work.
But what modern chemical testing may not unveil, old-fashioned interviewing may reveal, investigators say.
"We have people with backgrounds in art, who have worked in the art theft field for years," said special agent Paul Cavanagh, a spokesman for the FBI in Boston.
Likewise, the network of law enforcement agencies around the world has been put on alert, authorities say, to search for the paintings or any of the suspects involved. The FBI has given a detailed description of the stolen art not only to its 17 legal attaches around the world, but also to all other federal agencies.
And any tip, no matter how offbeat, will be explored, authorities say. "Anyone who stole this stuff could be in Iowa in three hours," said Quinn, "as well as in Europe in five or six."
Copyright Boston Globe