SALEM (AP) - The man accused of planting pipe bombs under four cars one day in August 2006 plans to use an insanity defense when his trial starts this week, his lawyers said.

Lonnie Glinski, 45, waived his right to a jury trial. His two-day bench trial will be before Marion County Judge Thomas Hart.

Authorities said Glinski rigged his ex-wife’s car with a pipe bomb in an attempt to kill her and gain full custody of their two children.

Glinski is also accused of planting three other pipe bombs under random vehicles he found in the Salem area. All the bombs were active and could have killed and maimed, police have said.

“We are in large part not going to dispute any of that,” said Salem defense attorney Stephen Lipton, who will represent Glinski with attorney Mark Geiger. “We’re conceding that he did these things, but he was insane at the time.”

Glinski faces 17 felony charges — 13 counts of attempted aggravated murder and four counts of unlawful possession of a destructive device.

He was arrested two months after the attempted bombings and has been held in the Marion County Jail ever since.

Deputy District Attorney Matt Kemmy declined to discuss the pending case.

The bombs were discovered on Aug. 10, 2006, the same day as a massive fire in downtown Salem.

Two were attached to cars parked at Salem Hospital and Tyco Industries in Dallas, and two were found lying in the parking lot of a Salem grocery store. A bomb squad disarmed the explosives, and no one was hurt.

But each time a bomb turned up, the city grew more anxious. Police urged motorists to inspect their cars before driving.

Prosecutors are expected to put investigators and explosives experts on the stand Monday to make the case against Glinski, Geiger said.

On Tuesday, mental health experts from the prosecution and defense will testify about Glinski’s sanity.

“It’s not much of a whodunit so much as a whydunit,” Geiger said.

If found guilty except for insanity, Glinski would be incarcerated in a criminal unit at the Oregon State Hospital.