A five-year-old boy wandering outside alone in the night led police to a troubling discovery inside a North Miami Beach home — and to the arrest of the child’s mother.

Authorities say the boy approached officers and calmly explained that he had been left by himself after his mother went to Walmart.

Britley Louis, 23, was arrested on March 8 and charged with child neglect and unlawful desertion of a child, according to the North Miami Beach Police Department. The case unfolded the night before when officers encountered the young boy outside and realized he appeared to be alone.

Body camera footage released by the department and shared by Law&Crime shows the moment the child approached police and began answering their questions.

“Are you by yourself?” one officer asked.

The boy replied that his mother had gone to Walmart.

“She didn’t tell me what time she would come [home],” he said.

When officers asked if he lived nearby, the child responded quietly that he did — and that he lived there alone.

“Mmhmm, by myself,” the boy said.

When pressed further, he explained the heartbreaking reason.

“Because my mommy left me.”

According to the arrest affidavit, officers observed the boy wearing only a long-sleeved T-shirt. He had no pants or shoes on. The child told officers where he lived and pointed them toward a nearby house.

Police attempted to make contact with someone inside but received no response. Eventually officers discovered an open door through which the boy had apparently exited.

Inside, investigators say they found disturbing living conditions.

The house showed “signs of hoarding,” according to the affidavit. Officers reported that the home was dirty and cluttered, with spiderwebs covering surfaces and “rotten food residue everywhere.”

The refrigerator emitted what officers described as an “unbearable” odor.

Authorities began attempting to reach the boy’s mother but said Britley Louis did not answer several phone calls from investigators.

Police later connected with the Florida Department of Children and Families, which launched its own response to ensure the boy’s safety.

According to the affidavit, Louis told a DCF agent that a friend of hers would come pick up the child. But when authorities contacted the friend, the woman reportedly told them she was not comfortable taking custody of the boy.

With no other immediate caretaker available, the child was placed into the care of DCF.

Louis was later taken into custody and booked on charges of child neglect and unlawful desertion of a child.

Court records show she was released from jail after her arrest but was ordered not to have any contact with her son.

The judge’s order bars Louis from seeing or communicating with the child while the case proceeds.

Her next court appearance is scheduled for April 7.