Girl, 2, shot dead in her mum's arms through living room window

Police at the scene of the fatal shooting in Philadelphia. [Mirror]

A little girl died in her mother's arms after she was shot in the head through her home's living room window, police in Philadelphia say.

Reports have named two-year-old Nicolette Rivera as the victim of the deadly shooting in the US state over the weekend.

A police spokesman told local media the toddler, her mum and a man were all hit when assailants opened fire through her home's front door and windows.

Nicolette was described by her mum as a star and a bright light in everyone's lives, NBC Philadelphia reported.

Nicolette's 24-year-old mum said she was planning to dress up her little girl as Baby Shark for Halloween, but has been left fighting for justice for her slain child.

The mum and a 33-year-old contractor inside the home cleaning carpets at the time were both also hit by gunfire, police said.

The pair were rushed to hospital, but Nicolette was pronounced dead at the scene.

Police said the mum sustained a gunshot wound to her left arm and a graze wound to her head, and she has since recovered.

The man was shot in the abdomen and is reportedly in a critical condition.

The Philadelphia Police Department reportedly suspects an assault rifle was used in the shooting.

Officers found six rifle casings outside the front of the house.

Detectives are reportedly probing a possible connection between the incident and another shooting about eight minutes earlier and around half a mile away.

Nicolette Rivera was shot dead in her living room. [Mirror]

Police told NBC in the earlier shooting two suspects opened fire on a black sports utility vehicle using an assault rifle and a .40 calibre hand gun.

In a separate incident, an 11-month-old boy was shot in the backseat of a car in Philadelphia on Saturday night.

Yazeem Jenkins was hit once in the chest and twice in the buttocks and remained in critical condition on Monday, local time, police said.

A $30,000 reward is being offered for information leading to an arrest or conviction in either of the cases, the city's officials told media on Monday.