Journal Sentinel staff

Some stood ramrod straight on sidewalks and street corners.

Some wore uniforms or caps that reflected public service — firefighters, veterans and police officers.

Some held signs — "We love and support you" — or held flags or quietly saluted.

And some just pulled their cars over and opened their windows to watch.

Under bleak, misty skies, crowds of people watched a silver hearse journey from the medical examiner's office to a Brookfield funeral home Thursday afternoon, transporting the body of slain Milwaukee Police Officer Matthew Rittner.

The 35-year-old officer, a 17-year veteran of the Milwaukee Police Department, was shot and killed Wednesday while serving a search warrant at a south side Milwaukee duplex.

A 26-year-old man, Jordan Fricke, was in police custody Thursday.

Questions about what happened and why it ended so tragically will continue to be asked in the coming days. But the overwhelming response the day after Rittner's death continued to be aching sorrow over the third Milwaukee officer lost in the line of duty in eight months.

Rittner leaves behind his wife, Caroline, a young son, a mother, a brother, a father-in-law, a law enforcement community and a city that seemed, at least for a time Thursday, to come to a standstill in mourning and respect.

Starting at 4 p.m., the procession carrying Rittner's casket made its way from West Highland Avenue to Miller Park, where Rittner was married two years ago, and then on to Krause Funeral Home on West Capitol Drive. Outside the stadium, the electronic digital billboard read: "Our thoughts and prayers are with you."

An hour after the procession started, Milwaukee's City Hall was lit blue in tribute to Rittner, thanks to Majic Productions. The city announced late Thursday that a vigil would be held Friday at 6:30 p.m. to honor Rittner and show support for his family. It will be in the auditorium at the Clement J. Zablocki School, 1016 W. Oklahoma Ave.

Further, Gov. Tony Evers ordered all U.S. and state flags to be flown at half-staff in honor of Rittner.

“This loss is also a reminder that men and women like Matthew put their lives on the line every day to protect our citizens and communities in Wisconsin," Evers said. "We are grateful for their bravery and call to service.”

Amid the mourning, more was learned about the suspect in the shooting.

Fricke bought and worked on firearms, enjoyed going to gun shows and practiced shooting at gun ranges, friends said Thursday.

Raised by his grandparents, he was a “couch potato,” the friends said, who regularly used marijuana and did not consistently have a job, instead spending his time fixing cars for resale.

Fricke had not been formally charged Thursday; prosecutors said police had not yet referred the matter to them.

Wednesday morning about 9 a.m., Rittner and other officers with the Tactical Enforcement Unit were serving a search warrant on Fricke at the duplex where he lived with his grandmother in the 1200 block of South 12th Street.

The warrant was part of an investigation into illegal sales of guns and drugs.

Officers repeatedly announced themselves as police; neighbors said they heard it over loudspeakers. When the officers tried to breach the door, Fricke fired several shots through the door, Chief Alfonso Morales said at a news conference Wednesday night.

Law enforcement sources told the Milwaukee Journal Sentinel the shots came from a high-powered rifle.

Two friends of Fricke's said Thursday that he regularly collected and accessorized guns, and that he had a concealed-carry permit. State law prohibits Department of Justice officials from revealing who has a concealed-weapon permit, but Fricke's record — several traffic citations but no misdemeanor or felony convictions — was not serious enough to prevent him from obtaining one.

Fricke attended Pulaski High School in Milwaukee from 2006 to 2010 and graduated from Groppi High School in 2011, according to Milwaukee Public Schools.

Longtime friend Mario Barry, 28, said he has known Fricke since he was 8 years old. He said Fricke has lived with his grandparents for as long as he could remember, and with just his grandmother since his grandfather died five or six years ago.

Barry said he never asked about Fricke’s parents, calling it a “touchy subject.” He knew only that Fricke’s mother died when he was very young, and his father was never involved in his life.

Barry said Fricke’s brother struggled with alcohol and drugs. Joshua Fricke, 25, died in 2015 after a night of drinking when he lay down in the middle of South 13th Street and was struck by a hit-and-run driver. The medical examiner ruled the death a suicide.

Fricke also has a sister.

Barry said Fricke was showing him pictures Tuesday night of a car Fricke had restored. He said fixing and selling cars was something they enjoyed doing together and that Fricke had always said he wanted to open a car shop.

Another friend, Juany Estrada, 28, said Fricke was robbed two years ago and spent most nights playing video games and watching movies and usually slept in until 11 a.m. or noon.

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Neither Barry nor Estrada thought Fricke used or sold hard drugs.

"We smoke weed, but he doesn't sell drugs,” Barry said. “He didn't affiliate with people who do drugs."

However, the Tactical Enforcement Unit routinely handles searches where there is knowledge of guns in a house, because of the heightened risk. And police did suspect Fricke of being involved in narcotics sales and illegal firearm sales.

Bruce Vielmetti, Annysa Johnson, Margaret Cannon, Jesse Garza, Ashley Luthern and Mike DeSisti of the Journal Sentinel staff contributed to this report.