"No other country in Europe is seeing anything like this," said Prime Minister Ulf Kristersson as he vowed to defeat the gangs.
"Swedish legislation was not designed for gang wars and child soldiers. But we're changing that now," he said.
Sweden's gang wars have smouldered for a decade over control of the drugs market.
But they took a drastic turn early this year when an internal feud led to gang members' families and loved ones also becoming targets.
The September 13 shooting in Cervin's building in Uppsala, 70 kilometres (45 miles) north of Stockholm, was aimed at the mother-in-law of Rawa Majid, the "Kurdish Fox", and head of the notorious Foxtrot gang.
She escaped unharmed.
- 'Ruthless' -
"I had no idea she was related to him," Cervin said. "That's what makes so many people scared -- the people involved have friends and relatives all over the place."
"This new generation (of criminals) is ruthless," said Garip Gunes, who started a youth football team to keep kids in the disadvantaged Stockholm suburb of Rinkeby out of trouble.
"Many parents are worried about their kids and don't let them go out except to go to school or football practice. They're worried they'll end up in the line of fire," he told AFP.
Criminology professor Felipe Estrada Dorner of Stockholm University told AFP the situation "has gotten totally out of control: they've started attacking loved ones and those who have nothing to do with these conflicts."
"This is a big change from the violence that has prevailed until now."
Forty-seven people have been killed in 314 shootings so far this year, police said, compared to only seven deaths in 2016.
- 'Failed integration' -
The victims and the perpetrators are increasingly young.
Police last year investigated 336 15- to 17-year-olds for having illegal firearms, eight times more than a decade ago, the National Council for Crime Prevention said this month.
Gangs now recruit kids to carry out contract killings -- some younger than 15 -- knowing they can't be jailed.
"Children are contacting criminal gangs" offering to commit murders, Sweden's police chief Anders Thornberg said.
These children "just don't know how to handle these weapons", Estrada Dorner said, often leading to innocent bystanders being wounded or killed.
In Gottsunda, a suburb near Uppsala, Ebtesam Abowarrad agreed, and said people were scared.
"The difference nowadays is that they shoot all over the place."
"I never see anyone out in the streets anymore," the 40-year-old mother told AFP.
Most young gang members have been on social services' radar for years, said Evin Cetin, a former lawyer who has written a book of interviews with young gang members, "Mitt ibland oss" (In Our Midst).
"These kids have been trained by criminals -- they live, eat and breathe a culture of violence," she said.
"Most of those I've met have an empty look in their eyes, they don't value their own lives."
Prime Minister Kristersson has blamed the rise in organised crime on "naivety" over immigration.
"An irresponsible immigration policy and failed integration led us here," the conservative leader said.
- 'Lost count' -
But Cetin argued that the integration problem has a lot to do with the segregation immigrant communities face.
"How is it possible that young Swedes in one of the richest countries in the world have gotten to the point where they're willing to kill, and kill their best friend to boot?" she asked.
"It says a lot about segregation, the conditions in which they grow up and the exclusion they experience."
Sakariya Hirsi, 26, who hails from Tensta, a heavily-immigrant suburb north of Stockholm, has seen several of his friends die in the violence.
In 2020, he founded the Kollektiv Sorg group (Collective Grief) to help families cope with their loss and lobby for change.
At a recent meeting of the group at a church in the suburb of Botkyrka, Alexander Zadruzny, 23, said he's "lost count" of how many of his friends have died.
"I used to say that our kids grow up too fast, but... our kids don't even live long enough to become adults."
Inhabitants of Grindavik carry out belongings from their homes after a series of tremors have set off a volcano alert © Kjartan TORBJOERNSSON / AFP
A crack cutting through the front of a house in Grindavik, southwestern Iceland, where earthquakes have heightened fears of a volcano © Kjartan TORBJOERNSSON / AFP