Suffolk County police said two brothers were fatally shot in Mastic Beach Friday afternoon.
Blake Chambers, 28, and his 22-year-old brother, Codi, were shot in their home at 12:25 p.m., police said.
The victims were taken to Brookhaven Memorial Hospital Medical Center in East Patchogue, where they were pronounced dead.
The William Floyd School District said in a statement on its website that all schools in the district activated lockout protocols at the time.
The district also said it was informed by Suffolk police that a suspect was in custody. A police spokeswoman could not confirm if a suspect had been apprehended.
Homicide Squad detectives are continuing the investigation and ask anyone with information on this shooting is asked to call them at 631-852-6392 or call anonymously to Crime Stoppers at 1-800-220-TIPS.