Authorities said Tran, of Oakdale, admitted shooting at the vehicles but did not say why.

A Minnesota man accused of standing in the street and firing at passing cars — killing a 9-year-old boy — had roughly 200 rounds of ammunition stuffed into his jacket pocket, a backpack and the fanny pack he was wearing when arrested, prosecutors said Wednesday.

Nhan Lap Tran, 34, was charged Wednesday with second-degree murder and other counts in Monday's shootings in the St. Paul suburb of Oakdale. Fourth-grader Devin Aryal died in the shootings, and his mother and another woman were wounded. Two other motorists escaped as they were being fired upon, according to the criminal complaint.

Authorities said Tran, of Oakdale, admitted shooting at the vehicles but did not say why. A Washington County District Court judge ordered Tran to undergo a mental health examination. Tran has no criminal record, and authorities have said they don't know of any past mental health issues.

"This case is simply a senseless tragedy," Washington County Attorney Pete Orput said. "We cannot comprehend a situation where a parent loses their child in any manner, much less in this way."

Along with bullets, Tran was carrying two loaded 9 mm magazines and two large knives when he was arrested. A loaded 9 mm handgun, with a bullet in the chamber, was found just feet from him. He admitted he tossed the gun aside when he saw authorities closing in, the criminal complaint said.

Fred Fink Jr., chief of the Washington County Attorney's Office Criminal Division, estimated Tran had close to 200 rounds of ammunition in his jacket and packs when arrested.

Tran's attorney, Susan Drabek, had no immediate comment because she had not received paperwork in the case.

Devin Aryal had just been picked up from day care and was riding home in a minivan when he was shot multiple times, including in the head. He died from his injuries. His mother, 39-year-old Melissa Aryal, was shot in the arm.

According to the complaint and in an interview, Melissa Aryal said she was driving Monday evening when she saw a man on foot shooting at her minivan. She realized she was shot and, while wounded, drove to the parking lot of a nearby Rainbow Foods. She then noticed Devin was slumped over — and she held him until an ambulance arrived.

"He didn't deserve this. He was just a baby," she said Tuesday.

Karen Knoblach, 68, was driving another vehicle with her three granddaughters — two 15-year-olds and one 20-year-old — when they saw a man shooting at them. Knoblach was shot in the leg and hand. She had to have part of a finger amputated but was in good condition at Regions Hospital on Wednesday.

Two other vehicles also were damaged by gunfire. One woman said she saw a man shoot five times at one vehicle, then turn his gun on her. The woman ducked and kept driving as gunshots hit her windshield, according to the criminal complaint. Police found three bullet holes in her front windshield, and one bullet had hit the headrest of the front passenger seat, the complaint said.

A man in another vehicle told police he saw a man in the street and realized he was being shot at when a bullet struck his windshield. The driver said he saw the gunman bend over as if he was reloading, so he quickly drove away, the complaint said.

A witness told The Associated Press that the gunman appeared calm as he walked down the block, firing his weapon.

"He was nonchalant," said Cheryl Russell, a neighbor who saw the shooting. "Just walking like he was out for a stroll. It was crazy."

Tran is charged with a total of six counts, including one count of second-degree intentional murder and one count of second-degree murder during an assault. He also faces charges of attempted murder and assault. Bail was set at $2 million.