Jurors in the Toyota liability trial in Minneapolis said Monday that they could not reach a unanimous verdict, but were told by federal Judge Ann Montgomery to keep deliberating.

The surprise development came at 11:15 a.m., when the jurors sent Montgomery a note that read, "At this point in time we feel unable to come to a unanimous decision." The jurors then left for lunch.

Montgomery called lawyers for both sides and convened a session at 12:30 p.m. She asked jurors to resume deliberations "to try to reach an agreement if you can do so without violating your conscience."

The jurors left the U.S. Courthouse in Minneapolis at 4:30 p.m. and will resume deliberations on Tuesday.

The trial involves a lawsuit filed after a June 10, 2006, crash in St. Paul in which a 1996 Toyota Camry rear-ended a 1995 Oldsmobile Ciera. Three people died as a result of the crash and the Camry's driver, Koua Fong Lee, served more than two years in prison for criminal vehicular homicide.

Lee, 37, and members of his family who were in the Camry joined with the families and passengers from the Ciera in the suit, which claims that defective equipment caused the Camry to accelerate suddenly.

Toyota says that the Camry accelerator worked perfectly and that Lee caused the crash by hitting the gas pedal, rather than the brakes.

The jury began deliberations Wednesday afternoon after a three-week trial.

It met again Thursday and Friday, then adjourned for the weekend, resuming deliberations at 9 a.m. Monday. After two hours and 15 minutes, it reported the impasse.

Montgomery read the jurors standard instructions given in the Eighth U.S. Circuit Court of Appeals to a jury that says it can't reach a unanimous verdict. "When you deliberate," Montgomery told the jurors, "you should be willing to re-examine your own views and change your mind if you decide that you were mistaken." She told them to take all the time they need.

Bob Hilliard, Lee's attorney, said in an interview after the session, "In complicated cases it takes some time and some deliberations to get to a unanimous decision on any one issue. I'm optimistic that they have gotten past that and are deliberating on other issues."

Toyota's attorneys declined to comment.

St. Paul attorney Bill Tilton, who has attended some of the trial, said he was not surprised that the jury was struggling. "There is strong evidence on both sides," he said.

Last summer, jurors reached an impasse in the defamation lawsuit filed by former Minnesota Gov. Jesse Ventura against the estate of Chris Kyle, the late author of the bestselling memoir "American Sniper."

Jurors in that case sent U.S. District Judge Richard Kyle a note saying they could not reach a unanimous verdict. Kyle sent them back to deliberate, but they remained split, and after consulting with both sides, Kyle asked the jurors if they could agree in an 11-1 vote. They said they could not, but they could agree on a 10-2 vote.

Not knowing how it would turn out, attorneys for both sides accepted the split, which turned out to be in Ventura's favor. He won a $1.8 million verdict, which is now on appeal to the Eighth Circuit.

Attorneys for Lee and the families have not specified the amount of damages they are seeking. But they asked the jury in closing arguments to consider the millions of dollars they said Toyota has spent defending itself in the case.