Police in Japan have raided the homes of a 67-year-old Japanese woman arrested on suspicion of poisoning her husband, as details of six former partners' deaths emerge in local media.
The raids on Chisako Kakehi's homes come a day after she was detained.
An autopsy on her 75-year-old husband, who died in December 2013 weeks after their wedding, had found traces of cyanide in his blood.
Police are also looking into the 2012 death of a previous partner.
Police visited Ms Kakehi's homes in Kyoto and Osaka on Thursday, where they confiscated capsules and wafers to wrap powdered medicine, as well as books on drugs.
News outlets said Ms Kakehi had met her husband named Isao, who had a life insurance policy, through a matchmaking service. He was her fourth husband.
Besides Isao's death, police are also investigating the 2012 death of Ms Kakehi's 71-year-old then partner, who collapsed while riding a motorbike.
Investigators found cyanide in his blood sample, said Kyodo. His death was initially attributed to heart disease.
Ms Kakehi's previous three husbands and three boyfriends were reportedly aged between 54 and 75 when they died.
Each death allegedly took place within a few years of marrying or starting relationships with her.
Following Isao's death, Ms Kakehi began a relationship with another 75-year-old man. He died in September after falling ill, following a meal with Ms Kakehi at a restaurant, according to Jiji Press.
AFP news agency reported that police are now working on a theory that she had a hand in the deaths of her previous partners.
"We can't say how many now... Given their advanced age, we have to proceed carefully to judge whether their deaths were actually the result of foul play or not," said the investigator.
Media reports have linked Ms Kakehi's partners' deaths to hefty insurance payouts, with one news outlet saying she had received hundreds of millions of yen over the past two decades.
But Ms Kakehi has denied such accusations, and had earlier said she was simply "doomed by fate" to suffer a series of deaths.
"If people suspect murder, I'd find it easier to bite my tongue off and die," she told reporters in March.