A rare Stradivarius violin, worth an estimated $6 million, was stolen by a thief who tasered concertmaster Frank Almond and sped away in getaway car, police said today.

Almond was walking to his car in the parking lot after a performance at Wisconsin Lutheran College with the Milwaukee Symphony Orchestra, according to a police report, when Almond was assaulted with a stun gun at about 10:20 p.m. on Monday.

The shock caused Almond to drop the violin he was carrying and the suspect took it and jumped into car driven by an accomplice, police said.

The vehicle was described as a late 1980s or early 1990s, maroon or burgundy, Chrysler or Dodge minivan. A description of the suspects were too generic to release, according to the Milwaukee Police Department.

"It appears at this time that the violin was in fact the primary target of this robbery," Milwaukee Police Chief Edward Flynn said at a news conference on Tuesday.

Mark Niehaus, president of the Milwaukee Symphony Orchestra, said during the news conference that Almond "is in good condition."

Milwaukee Police Department

"No one ever wants to be tasered. He is recovering from that," Niehaus said.

This was the only Stradivarius violin in the orchestra and in Milwaukee, Niehaus said.

"We make art and we make wonderful art in Milwaukee. And part of our art are these instruments that were made for musicians hundreds and hundreds of years ago, and we continue to play these instruments in the tradition that they were built in. These instruments need to be played to live on," Niehaus said.

Constructed in 1715 and known as the "ex-Lepinski," the "violin is very valuable but very valuable to a very small population. This is not something that can be easily sold for even a fraction of its monetary value," Flynn said.

The violin has been entered into the international art theft database, police said.

The Milwaukee Police Department is working with the FBI's Art Crimes Team, and the FBI is working with Interpol to connect with international art dealers who will be able to help locate stolen items throughout international markets, police said.

"They will be monitoring their databases as this theoretically could be an international crime," Flynn said.

Milwaukee Police Department spokesman Lt. Mark Stanmeyer told ABC News today that "the suspect has not been identified and the violin has not been recovered."

According to ABC Milwaukee affiliate WISN, "police said Almond's iPad and the violin case were dumped on the street near Washington Park," near the scene of the crime.

Master instrument builder Antonio Stradivari was born in 1644 and established his shop in Cremona, Italy, according to the Smithsonian Institution. In addition to violins, Stradivari also made harps, guitars, violas and cellos, amounting to more than 1,100 instruments in all. About 650 instruments survive today.