The first half of a double-barreled grand-jury indictment was unsealed Wednesday when a Coon Rapids man was charged with drive-by shooting in a June road-rage incident in which he said he wounded an undercover Robbinsdale officer in self-defense.

Martin Treptow, 35, also was charged in Anoka County District Court with two other felonies: making terroristic threats and reckless discharge of a firearm.

Another court hearing is set for today for officer Landen Beard, when additional charges could be unveiled.

After the indictment, Treptow's attorney, Kurt Glaser, said his client will use a self-defense argument at trial. "He did what he thought was the right thing to do at that moment -- protecting his family," Glaser told reporters outside the Anoka County Courthouse. "He was faced with a crazy person driving down the road who confronted him and pulled a gun."

Beard, 26, was shot in the leg. He told authorities that Treptow pulled his gun first after they got into an argument on the afternoon of June 7. The incident occurred in Coon Rapids, not far from Beard's home. Beard, who has continued working undercover for Robbinsdale police, has never commented publicly on the case.

Treptow, a security business manager who has a gun permit, reacted that day as he had been trained to do as a security guard and bodyguard, Glaser said.

Treptow and his wife told police that Beard pulled a gun as he sat in a car right next to them and aimed it at Rebecca Treptow, who was seated in the front passenger seat by her husband. Their two children, ages 6 and 5 months, were in the back seat. Treptow drove away and called police minutes later to report the shooting near 99th Avenue and Foley Boulevard.

He said Beard was in plain clothes and an unmarked car and did not identify himself as an officer. Treptow was arrested and jailed overnight before being released without charges.

An Anoka County grand jury heard evidence in the case for two days last week; its decisions were sealed until this week. Treptow voluntarily testified before the grand jury and answered a prosecutor's questions, said Glaser.

Judge Michael Roith released Treptow on his own recognizance after a brief court appearance Wednesday. Release conditions include no contact with Beard and a requirement that he turn over any firearms to police.

Glaser said Treptow had already gotten rid of his guns.

Rebecca Treptow, who also testified before the grand jury, appeared at Wednesday's hearing but had no comment afterward. Her husband was booked and released at the county jail and could not be reached for comment.

Jim Adams • 612-673-7658