A 2-year-old Brentwood girl drowned in a relative’s above-ground pool Friday afternoon, Suffolk police said.

Arlyn Vanegas-Luna was taken by Brentwood Legion Ambulance to Southside Hospital in Bay Shore, where she was pronounced dead. Someone called emergency personnel shortly after 4:30 p.m. when she was found unresponsive in the backyard of a home at 101 Chestnut St., police said.

advertisement | advertise on newsday

Authorities said the girl lived next door to the home, where police said at least one of her relatives also lives.

Police did not provide details about how the toddler ended up in the pool but said the incident was under investigation by Suffolk’s Homicide Squad detectives.

It was unclear Friday night whether any charges would be filed in the case.