A FedEx worker rescued a five-year-old boy who was left alone in a rat infested, feces covered apartment in the Bronx.

The boy's parents, Wilfred Lewis, 59, and Charlotte Lewis, 48, were arrested after the delivery worker knocked on the door of the Kingsbridge Ave apartment around 11.30am Friday morning and found the boy alone.

When the little boy answered, the FedEx worker asked where his parents were.

The five-year-old responded, 'They're not home.'

The view of the hellish conditions inside the rat infested, feces covered apartment in the Bronx where a five-year-old was left to fend for himself

Charlotte Lewis, 48, (pictured with her children) is a nurse at Montefiore Hospital, police arrested her there on Friday

The door to apartment 2J where a FedEx worker discovered the boy, 5, is pictured

The worker left the building and flagged down an officer for help, according to the NY Post.

When police broke open the door they say they found the child alone in the apartment with feces smeared on the walls, roaches, bed bugs, maggots and even rats running around.

The boy told police he had not seen his parents since Thursday night.

Authorities say the horrific conditions were made worse by the fact there was no food in the fridge, according to the New York Daily News.

The parents' three other children, a 12-year-old girl, a 13-year-old girl and a 15-year-old boy were not home either.

Charlotte, a nurse at Montefiore Medical Center, was arrested at work.

Wilfred, a Metropolitan Transportation Authority technology trainer, told police his five-year-old son was 'self-sufficient,' and was home sick from school.

The father surrendered at the 50th Precinct.

Charlotte and Wilfred are charged with failing to exercise control of a minor.

The boy's father is also being charged with child endangerment.

All of the children were taken to Montefiore Hospital, where their mother was arrested, to be treated.

The squalid apartment where the boy was left alone was in this building in the Bronx

Wilfred and Charlotte Lewis' four children are currently in the care of the Administration for Children's Services

They are all currently with the Administration for Children's Services, which had previous contact with the family.

In a statement to ABC7, ACS' Deputy Commissioner for External Affairs Eric Ferrero said: 'Our top priority is protecting the safety and well-being of all children in New York City.

'We are working with the NYPD to investigate this incident, and the safety of all of the other children who were in this home has been secured.'