The 30-year-old woman’s lawyer, Eva Möller, confirmed for the TT agency that her client is currently being held on suspicion of having killed the two boys.

“I don’t want to comment further on her mental state. But she has just lost two children,” said Möller, who added that she met with her client Monday evening following her arrest.

“At that time they had held a short interview where she was informed of the suspicions against her. No additional interrogations were held after that and no more are planned.”

The woman was allegedly down near the shoreline with the two boys, ages 4 and 8, on Sunday night when something happened.

“She said that she heard a thud when they were down by the water and that suddenly, the boys were gone,” the father of the 4-year-old told the Aftonbladet newspaper.

He said he received a call from his ex-partner on Sunday night in which she said that “something unpleasant and strange” had happened to the children.

The father rushed from his home in southern Stockholm to Sigtuna where he found the boys’ mother in a state of shock.

“It was like talking to an empty hole,” he said.

The suspected mother also participated in the early search for the boys, who were first reported missing around 10pm on Sunday evening.

Police intensified their search on Monday morning after conversations with people in the area led them to believe that a crime had been committed.

The boys’ mother was arrested shortly before 11am as police made additional observations that strengthened suspicions that the boys didn’t disappear willingly.

The first boy’s body was recovered around 12.30pm on Monday. A short time later, divers located the body of the other boy.

Autopsies will be performed on the bodies of the two boys later in the week, according to police spokesperson Stefan Marcopolus.

He also expected the boys’ mother to be questioned further.

“The woman will be interviewed again in the coming days, but no time has yet been set,” Marcopolus told TT.

Police investigators are reluctant to release many details of their investigation, which is in an early and sensitive phase.

However, police are hoping to make contact with witnesses who may have been nearby the Munkholm bathing area in Sigtuna between 6pm and midnight on Sunday evening.

“The witnesses we’ve interviewed so far have strengthened our suspicions that a crime was committed,” said Marcopolus.

According to neighbours, the habits of the woman and her two boys changed drastically about a month ago.

“The blinds were suddenly pulled down and the children disappeared from the playground,” a neighbour told Aftonbladet.

The 4-year-old’s father also told of receiving a call from his son’s daycare inquiring as to the boy’s whereabouts.

“They asked what had happened to the boy since he hadn’t been back since the end of summer vacation,” he said.

The father was unable to reach the boy’s mother to discuss the matter.

“In retrospect, I think I should have contacted the police sooner,” he said.