Portuguese police have launched a new smear campaign against Kate McCann via the Portuguese media

Detectives trying to prove that Kate McCann killed her daughter have painted the 39-year-old doctor as a violent mother prone to "hysterical reactions" and losing control.

The allegations were leaked to Portuguese newspapers hours after Mrs McCann and her husband Gerry left the country under a cloud of suspicion about the disappearance of four-year-old Madeleine.

Quoting police sources, the papers alleged that Mrs McCann became "visibly out of control" under questioning by police, and that witnesses had described her as "violent" and "aggressive" towards her children.

It was claimed that she routinely put Madeleine and the two-year-old twins to bed in the family's holiday apartment "while Gerry played tennis and lay by the pool".

The reports also quoted witnesses who have given statements to police.

Pamela Fenn, who was in an apartment above the family on May 3 - the night Madeleine disappeared - is quoted as saying she believed Mrs McCann sometimes became violent and "out of control" in the room below.

She claimed that "the little girl's screams calling for her daddy were very audible".

Another witness is quoted as saying that Mrs McCann "seemed to have moments of aggressiveness towards her children" and that her husband, "though more absent, had more emotional control".

Mrs McCann is said to have strongly denied both these allegations in police interviews.

The damaging picture painted by Portuguese newspapers emerged as police sought to convince the public prosecutor that they have a strong enough case to charge Mrs McCann over the murder or accidental death of her daughter.

The McCanns have repeatedly insisted they are loving parents who had nothing to do with Madeleine's disappearance. They are convinced police are trying to frame them.

But the allegations, strongly denied by the family, risk poisoning public support for the couple and stopping donations to the "Find Madeleine" campaign they set up.

Portugal's secrecy laws prevent police from talking about the investigation, but the leaked material appears to contain specific information about interviews conducted with the McCanns last week.

It was claimed that Mrs McCann became "hysterical" at times during her 13 hours of interrogation and refused to reply to some of the questions.

It was alleged that she offered no explanation for why Madeleine's DNA appeared to have been found in a car the couple hired 25 days after she vanished.

Nor is she said to have given any satisfactory answer to whether she had slapped her daughter, or whether she sedated the children.

The Portuguese police are reported in the newspapers as having concluded that Madeleine was killed by accident.

They believe that her parents then hid her body in their car boot in the compartment for the spare wheel.

The four-year-old's blood was found under the carpet of their hired Renault Scenic in the place of the wheel, the daily Correi da Manha reported.