The Coast Guard said in a statement on Friday that the helicopter went missing on Thursday evening.
“They stated the aircraft was due back at 5:21 p.m. from a tour of Kauai’s Nā Pali Coast with one pilot and six passengers,” the statement noted. Two of the missing passengers were children.
The statement added that the helicopter was equipped with an electronic locator but no signals had been received.
An official at the Joint Rescue Coordination Center called weather conditions challenging.
“The weather conditions are challenging,” said Petty Officer First Class Robert Cox, Coast Guard Joint Rescue Coordination Center Honolulu.
“We have trained crews responding and on scene searching for any signs of the helicopter and those aboard,” he added.