A woman who took care of alleged Florida school shooter Nikolas Cruz after his mother died, has said she warned police multiple times about “warning signs” in his behaviour, including one instance where he put a gun to his family members’ heads.

Rocxanne Deschamps was close friends with Lynda Cruz, the adoptive mother of both Mr Cruz and his brother, Zachary. At a press conference on Tuesday, she said she had cared for the boys for a little less than a month after Ms Cruz died in 2017 – until Mr Cruz’s obsession with guns forced her to kick him out.

Among other things, Ms Deschamps said Mr Cruz was “very depressed” after his mother’s death, and refused to take his medication or seek treatment. She said she had personally seen him punch holes into walls, and heard from his mother that he had put a gun to her head. When she told police about this, she said, they did little to help.

Ms Deschamp’s lawyer, women’s rights attorney Gloria Allred, said her client wanted to “share her truth about what really happened” in the month Mr Cruz lived with her. Both Ms Deschamps and the local sheriff’s office have been criticised for not doing more to stop the troubled youth from obtaining and using weapons.

Mr Cruz has been charged with 17 counts of murder and a plea of not guilty was entered.

The press conference took place shortly after Zachary Cruz was arrested on the grounds of Marjory Stoneman Douglas High School – the same school where prosecutors say his brother shot and killed 17 people last month. Zachary was arrested and charged with trespassing on school grounds.

The 18-year-old has lived with Ms Deschamps throughout the ordeal, even after his brother moved out. Ms Deschamps has reportedly petitioned for control of his mother’s estate, claiming she was “caring for a 50 percent minor beneficiary”.

Florida shooting – in pictures Show all 10 1 /10 Florida shooting – in pictures Florida shooting – in pictures Police arrest a suspect in connection with the shooting at the Marjory Stoneman Douglas High School in Parkland, Florida Reuters Florida shooting – in pictures Parents wait for news after reports of a shooting at Marjory Stoneman Douglas High School in Parkland, Florida AP Florida shooting – in pictures Anxious family members wait for news of students AP Photo/Wilfredo Lee Florida shooting – in pictures Students being evacuated from the school AP Florida shooting – in pictures Students being evacuated from the school Getty Florida shooting – in pictures People gather waiting for word from students AP Florida shooting – in pictures Parents waiting for news on their children AP Florida shooting – in pictures People gather at a hotel where students were taken after the shooting Getty Florida shooting – in pictures Florida Governor Rick Scott speaks to the media as he visits Marjory Stoneman Douglas High School following the shooting AFP/Getty Florida shooting – in pictures Dr. Igor Nichiporenko, Medical Director Trauma, left, and Dr. Evan Boyer, Medical Director, Emergency Services, speak about treating victims and the suspect at a press conference outside Broward Health North hospital AP

On Tuesday, Ms Deschamps detailed the tumultuous time period after Mr Cruz and his brother moved in with her, in which she claims to have placed at least three 911 calls in less than a month.

In one instance, Ms Deschamps said she called the authorities because her mother found receipts for a gun and bullets in Mr Cruz’s bedroom. In another, the women discovered a hole in their backyard, as well as a large empty gun box with dirt on it. Assuming Mr Cruz was trying to bury weapons, they called the police.

In another instance, Ms Deschamps said Mr Cruz and her teenage son got into a fight, which turned physical. When Mr Cruz ran away, she worried he would come back with a gun. When he eventually returned, she gave him a choice between living in her house or keeping his gun. He chose the gun, she said.

“I told the police about prior incidents that I knew of in which Nikolas had put a gun to his mother’s head and to his brother’s head. I also told them about other warning signs,” Ms Deschamps said on Tuesday. “...Law enforcement said nothing could be done.”

Florida shooting suspect Nikolas Cruz appears in court the day after mass shooting

The sheriff’s office is already facing allegations that it did not respond adequately to warnings about Mr Cruz’s behaviour. The office has admitted that it received at least 23 phone calls about Mr Cruz or his brother between 2007 and 2018 – including one in which a neighbour’s son warned Cruz planned to “shoot up” a school.

Further investigation by CNN show the number of calls may have been as high as 45. A log of the 23 phone calls the sheriff’s department says they received about Mr Cruz does not include the calls Ms Deschamps claims to have made.

The Broward County Sheriff’s office did not respond to a request for comment. In a previous statement posted to their website, the department emphasised that 911 calls do not equate to a crime being committed.

“There were no arrestable offences, nor was there evidence to prompt an involuntary mental health assessment,” the department said of Mr Cruz. ”The shooter was assessed several times by mental health professionals and deemed not to be a threat to himself or others.”

Ms Deschamps did not respond to questions about her bid for control of the Cruz brothers’ inheritance. The New York Post reported last month that Ms Deschamps had filed paperwork to assume control of Ms Cruz’s estate the day after the shooting.

Ms Allred directed all questions about the estate to an attorney for Zachary. The attorney, Jose Lorenzo, did not respond to a request for comment.

Earlier that same day, police say Zachary walked onto the grounds of Marjory Stoneman Douglas, saying he wanted to “reflect on the school shooting and soak it in”, according to an arrest report. He was arrested and charged with misdemeanour trespassing. Bail was set for $500,000.

Ms Deschamps would not say whether the teenager would return to live with her after his release.