The search for a 27-year-old experienced hiker who disappeared 10 days ago after taking off on a solo hike for the first time in Hawaii has intensified as the family of another missing hiker announced a reward for information on her disappearance.
"He never hiked alone. And he said, 'I wanna try it,'" his father, Steve Brittain, told ABC News on Saturday.
Kyle Brittain was last seen near the Waipio Valley lookout area on Aug. 30, according to Hawaii police.
Steve Brittain said that the family had never hiked that particular trail, which was a 1,000-foot cliff at a 70-degree angle.
"He had informed family members that he was going hiking for the day on the transverse trail in Waipio Valley towards Waimanu Valley," police said in a news release on Sept. 3. "[Kyle] Brittain is described as being 5-feet-11-inches, 145 pounds, with brown hair and eyes."
His father said Monday that his cellphone last pinged around noon Aug. 30. His vehicle was parked at the trail's entrance but his keys couldn't be found, his family said.
"I said, 'Hiking alone is not the best idea, but you're not doing a long hike,'" Steve Brittain said he told his son before he departed for the hike. "He's been hiking since he was 3, so this is not a new adventure for him."
Steve Brittain said that before Kyle Brittain left, he told his family exactly where he'd be and when to expect his next call.
"He's read survival-skill stuff. … I think, like any 27-year-old boy who enjoys outdoor activities, he thinks he has them, but he's never been called on to use them," Steve Brittain said.
Search teams have been looking for Kyle Brittain by land and air. They've also grown in size, having added helicopters, dogs and rescuers, like Javier Cantellops.
"You know, this is a very large area so we're just trying to make sure that Kyle didn't push really far in," Cantellops told ABC News. "I never lose hope of finding him. I mean, Amanda was a perfect example of that, you know, of never losing hope."
It rained on the day that Kyle Brittain disappeared, so his family said there was a possibility that he'd slipped and gotten injured in the valley. They said there is also very little cell service in that area, which would explain why his phone stopped pinging.
"I have to be optimistic...we all are," Steve Brittain told ABC News. "He wasn’t equipped to do an overnight hike. If he's out there surviving, which we hope he is, it's pretty bare essentials he's working with. … We're all going to be here until we find him."
Meanwhile, police in Maui are continuing to search for Khiara Henry, 23, of San Diego, whose family reported her missing on July 26 after she visited the island on vacation.
On a Facebook page dedicated to finding Henry, her family said that she'd been staying at a hotel in Kihei. On July 21 at 2 p.m., she then rented a car for one night to visit Hana's Waianapanapa State Park.
"The last confirmed sighting of Henry was on July 21st 2019 when she rented a car in Kahului. Her car was later found in the Waianapanapa Park area," Maui police said in an Aug. 5 news release posted on Facebook. "Police and community search efforts in the Waianapanapa Park and surrounding areas have so far been unsuccessful. We would like to thank the Maui Search and Rescue members for their tenacious efforts in trying to locate Khiara."
Her family said that the car held her luggage, as well as her credit card and ID.
"Her cell phone, small backpack and car key were not in the car and have not been located," her family said on the Find Khiara Henry Facebook page on Saturday. "Khiara’s cell phone goes straight to voicemail and has not been used since prior to her disappearance. Her credit card and banking activity also stop on July 21st. Khiara did not appear for her flight home on July 29th."
Henry was described as 5 feet, 3 inches tall, and 120 pounds with brown eyes and brown hair.
On Saturday, Henry's family announced that it was offering a $10,000 reward for information leading to Henry's whereabouts.
ABC News' Kelly A. Landrigan, Alyssa L. Pone and Nick E. Cirone contributed to the reporting in this story.