A group of young backpackers who disappeared within the area where a Placer County forest fire is burning are safe, officials said Monday. The Placer County Sheriff's Office said the 13 backpackers, between the ages of 16 and 19, were all accounted for after a helicopter spotted them just after 7 a.m. None of them were injured."When we were close to it, I was thinking of all the possibilities of what could happen," said Michael Tait, 19.The sheriff's office said a search and rescue crew dropped in and hiked with them to the end of a trail at Cascade Lakes.Ty Conners with the sheriff's office said deputies on Sunday found four vehicles belonging to the backpackers in the Royal Fire zone. Conners said they contacted the vehicle owners to learn how many people were in the vehicles. Karla Hurd, who has two sons in the group, got that call."We didn't know if they were caught up in the fire or trying to outrun it back to their cars," she said. "We weren't sure how they were handling the situation."Hurd said messages to the satellite phone were not going through."That was frustrating because had we known they were OK, it would have saved some heartache," Hurd said. When they could not get ahold of the group, Conners said officials tried searching Sunday night using aircraft equipped with both night and heat vision.Conners said the four vehicles were found at the Palisades Creek trailhead, located at the southern border of the burn area. The sheriff's office said the group intended to go camping on the opposite side of the burn area, but the trailhead was caught in the flames.The northbound trail ends at Cascade Lakes, so Conners said deputies hoped to intercept the group as they headed south from the lakes. When the backpackers' parents couldn't get ahold of their sons, they headed to the trail to wait for them to return. They finally were reunited just before 1 p.m. on Monday."Relief, so relieved, so happy," said Jack Henna, father of a 19-year-old. "It was the period of time where I didn't know what was going on. I know they are capable kids but it was pure relief."Some of the teens jumped into Cascade Lake to relax after their all-night ordeal."We're just happy to be back here and swam in the lake and we're good," said Tait.One of the older hikers, Griffin Hurd, 19, is familiar with the trail and knew how to get away from the fire. They hiked an extra five miles to get to the other side. Much to the relief and joy of their parents."We knew they were OK and they were safe so that was a huge relief when we heard that," said Hurd. "But getting eyes on them was good."Tait said they talked about everything throughout the night and even slept a little bit."What I was thinking about mostly is how life is like really precious and s--t can go wrong real fast," he said. The teens live in the Arden Park area of Sacramento and have been friends since kindergarten. They've done this four-day camping trip for the past three years and plan to go back next year. The Royal Fire started Sunday in the Tahoe National Forest west of Soda Springs near Soda Springs Road. Five homes are under an evacuation warning, which means residents are not required to leave but are recommended to do so in case fire conditions become dangerous. Smoke from the fire was visible from Interstate 80 when it first started. As of Monday, smoke was not as visible, with mostly some haze present. Crews said the fire continues to burn in a remote area that is difficult to access.As of Monday, the fire has burned 169 acres and had no containment. Containment is not used to measure how much of the fire is out, but it is used to define how much of a perimeter is established around the burn area to prevent flames from spreading.The Tahoe National Forest said the cause of the fire is under investigation.| MORE | A 2024 guide for how to prepare for wildfires in CaliforniaHere are key websites that are important for all Californians during wildfire season.Cal Fire wildfire incidents: Cal Fire tracks its wildfire incidents here. You can sign up to receive text messages for Cal Fire updates on wildfires happening near your ZIP code here.Wildfires on federal land: Federal wildfire incidents are tracked here.Preparing for power outages: Ready.gov explains how to prepare for a power outage and what to do when returning from one here. Here is how to track and report PG&E power outages.Keeping informed when you've lost power and cellphone service: How to find a National Weather Service radio station near you.Be prepared for road closures: Download Caltrans' QuickMap app or check the latest QuickMap road conditions here.