A 16-year-old and an 18-year-old drowned in separate incidents while swimming in the Rockaways on Friday, officials and sources said.

A boy swimming at 100th Street Beach was pulled from the water by FDNY responders with assistance from NYC Parks Parks Enforcement Patrol, the city Park’s Department said.

A girl was pulled from the water by civilians at 108th Street Beach.

Both were transported to a local hospital where they were pronounced dead, authorities said.

The teens had been swimming in prohibited areas, Parks officials said. They were also in water after 6 p.m., when lifeguards leave for the day.

“We are heartbroken by these unfortunate deaths,” the Parks Department said.

“This is a painful reminder that New Yorkers should never enter the water in closed sections of our shoreline, where lifeguards are not present. We implore New Yorkers to only swim in open sections and when lifeguards are on duty.”

Closed sections of Rockaway Beach are marked with signs and red flags.