A large police force as well as an animal expert from Stockholm’s Skansen open-air museum were dispatched to the flat to help free the woman and her child.
The two victims were threatened by a 43-year-old man, who owned six green Asian pit vipers and two puff adders.
The man told the woman that he would release the snakes if they tried to leave the apartment.
Eventually, the man gave up, newspaper Expressen reported on Monday.
However, before police technicians ventured into the apartment, celebrity animal expert Jonas Wahlström took care of the snakes.
Wahlström is also the director of the Skansen Aquarium.
“The police asked me to take care of the snakes. I found only eight – a snake may have escaped,” Wahlström told the newspaper.
Police snuck into the apartment and successfully freed the woman and her child.
The green-coloured Asian pit viper is dangerous to humans and its venom can destroy red blood cells, disrupt blood clotting and cause organ degeneration and generalized tissue damage.
Injury from a hemotoxic agent is often extremely painful and can cause permanent damage. Loss of an affected limb is possible even with prompt treatment.
Separately, the puff adder is considered Africa’s deadliest snake and can grow to more than two metres long. It is responsible for the most snake deaths in Africa and its venom is enough to kill four to five people.
There was already a large police presence around the woman’s apartment early on Sunday after she had alerted them of her situation. The police knew a rescue attempt was risky given that poisonous snakes were involved.
“We have classified the crime as unlawful detention. However, I cannot say any more because there is much more to do in the investigation and more will be revealed,” Ove Svantesson, officer in command at Söderort police, told Expressen.
Officers likened the apartment to a “garbage dump” full of debris, including empty bottles, trash and cigarette butts. In addition to the snakes, there were also two lizards, one a half-metre long, the other one metre, the report said.
According to Wahlström, the lizards were left behind in the apartment and their fate will be determined by a prosecutor on Monday.