Marsha Mayes used to call the police every Monday to see whether anyone had been arrested for killing her 3-year-old son. Now, with no sign the case is any closer to being solved, she's stopped calling.

"They haven't made progress," said Mayes, speaking this week from her family's new home in a suburb of Minneapolis. "There's no leads."

The day after Christmas, Terrell Mayes Jr. and his brothers ran for the safety of an upstairs closet when gunfire erupted in their north Minneapolis neighborhood. A bullet that came through the wall struck Terrell in the head as he climbed the stairs.

The case brought extraordinary attention to the problem of stray gunfire in some Minneapolis neighborhoods, including Hawthorne, where Terrell was shot. A $10,285 privately funded reward and a $1,000 Crime Stoppers of Minnesota reward remain unclaimed. Billboards with Terrell's face went up around the city.

Despite Marsha Mayes' concerns that the case has stalled, Minneapolis police investigators Sgt. Tammy Diedrichs and Sgt. Barbara Moe remain dedicated to solving it, said Lt. Richard Zimmerman, head of the city's homicide investigation unit. "It's a top priority with our investigators," he said, although he also acknowledged its complexity.

"Of all the cases that I've seen in 17 years here, this is the toughest case and the toughest kind of case," said Zimmerman. "It was so indiscriminate."

The working theory is that some kind of gun battle erupted that night around the corner from the Mayes' home.

A bullet fired in an alley a block away missed its target and traveled on, piercing the wall of the Mayes house.

Investigators have mapped out friendships, alliances and rivalries in the neighborhoods near the homicide scene, hoping to uncover who was fighting that night. That's how Zimmerman, along with Diedrichs, cracked a similar slaying in 2002.

Tyesha Edwards, 11, was struck by a stray bullet in south Minneapolis while doing her math homework on a Friday afternoon at the family table.

The investigators found her killer by first tracking down the person he tried to shoot that day, said Zimmerman.

So far in the Mayes investigation, several people have been interviewed, though none of them would be considered suspects, he said.

It's possible that the shooter didn't realize at first that he had struck someone, but it seems likely that he would know by now, said Zimmerman.

No weapon has been recovered, and authorities haven't disclosed what type of weapon was involved, other than that it was high-powered.

The bullet that killed Terrell was heavy, his mother said.

"From the entry wound that I've seen, you would think it was small, but when that medical examiner dropped that thing in that tray and I heard it, that wasn't small," she said.

Anxiety amid uncertainty

Mayes has three other sons ages 12 to 2. Terrell was her second youngest. She said her two older boys, ages 12 and 11, don't sleep well and require curb-to-curb transportation to school. Her 2-year-old, Marrell, still asks for his older brother, who he called "Juju."

"He'll put on Juju's shirt and go to sleep in it," said Mayes. Her fears of continued gunfire in north Minneapolis scared her away from the house she rented on Colfax Avenue, and she sees no reason to move back. The family had a recent panic attack when fireworks were set off near their new house. Her sister thought someone was shooting at them, and for a few frantic seconds Marsha Mayes and her sons feared the same. Now she wants to move her family farther from the city.

Still, Mayes said she returns often to Minneapolis to keep talking to people who might know something about her son's death.

"That was my child, so I'm going to keep my feet to the streets," she said. If she gets something substantial, she said, she'd call the investigators.

She called once before with a lead, but it didn't move the case very far, she said.

Mayes remains convinced that someone saw something, given that most people rush to their windows to see who's shooting when they hear gunfire.

She's spent hours wondering if the killer is a young person or an adult, if they realize they killed someone, and if so, if they feel remorse.

"I just hope one day they come forward and say, 'Look, I did the shooting,'" she said.

She plans to have Terrell's fourth birthday party this summer in the neighborhood where he was shot.

Terrell was cremated, and his urn sits at her new home on the top shelf of a bookcase decorated with his favorite SpongeBob SquarePants pillow, teddy bears, toys and pictures. Also on display is the trophy awarded after his death that names him the "MVP" of the Farview Park Cardinals basketball team.

"He's here with me; he's in the same house," she said, looking up to the urn, "but Junior's not rested. Junior's soul is still at 2644 Colfax."

Matt McKinney • 612-217-1747