By Atossa Araxia Abrahamian

(Reuters) - A 4-year-old New Jersey boy shot and killed a 6-year-old playmate with a rifle he found in his family's home, police said on Tuesday.

The shooting in Toms River, New Jersey, on Monday, came two days after another 4-year-old shot and killed the wife of a sheriff's deputy at her home in Lebanon, Tennessee, using a handgun he found on a bed.

Both shootings were under investigation but believed to be accidental, authorities said.

Toms River Police Chief Michael Mastronardy said the children were playing with a golf cart outside the 4-year-old's home when the younger boy went inside and got a .22-caliber rifle.

The boy then either pulled the trigger or discharged the gun by accident, striking his friend in the head.

The 4-year-old's mother called 911 and the older boy was rushed to Jersey Shore Medical Center in Neptune, New Jersey, where he died at 5 p.m. on Tuesday, Mastronardy said.

The victim was identified as Brandon Holt of Toms River, police said.

Mastronardy would not comment on whether the weapon belonged to a licensed gun owner, saying the matter was under investigation. He urged gun owners to secure their weapons.

He said it would be up to Ocean County, New Jersey prosecutors to decide whether charges would be filed in the case.

President Barack Obama has been pressing Congress to pass stricter gun control laws after the elementary school shooting in Newtown, Connecticut, that left 20 children and six adults dead.

(Additional reporting by Ellen Wulfhorst; Editing by Barbara Goldberg, Bill Trott and Doina Chiacu)