Firefighters planned to continue their third day of searching Monday for a missing teenage boy who was hiking by himself in Waianae.

Richard Vierra Jr., 15, went hiking alone in the trails near his home on Ala Akau Street about 6:30 a.m. Saturday, according to a CrimeStoppers release. He called his mother about 11:30 a.m. to say he was returning home, but never arrived.

About 20 firefighters searched by land and air for the boy Sunday, along with police, family, and friends, said Honolulu Fire Department Capt. David Jenkins.

Firefighters suspended their search for the day at about 6 p.m. Sunday after no sign of the boy was found, Jenkins said.

He said the boy’s mother called for help about 1 p.m. Saturday, and firefighters began looking for the boy by working their way down from the top of the trail. A fire helicopter also assisted by dropping off firefighters along the trail and scanning from above.

Jenkins said firefighters called off the mountain search about 4:30 p.m. Saturday after authorities received information that a cell phone tower received a ping from the boy’s cell phone near Pokai Bay. Police searching in that area, but the boy was not found, Jenkins said.

Sunday morning, authorities followed up with cell phone company officials, who said it was possible the boy was still in the mountains and the tower received a ping because the boy was in a position where his cell phone’s signal reached the tower.

Jenkins said firefighters resumed their search in the mountains about 9:30 a.m. Sunday.

Firefighters scoured the trail where the boy was supposed to be, calling out to him and looking into crevices and over trail edges in case he fell and was injured, Jenkins said. Firefighters completed searching the area and will began Monday by interviewing the boy’s mother again for other areas to check.

Vierra is described as Caucasian, 5 feet 5 inches tall, and 120 pounds, with short reddish hair and brown eyes. He was last seen wearing a dark blue shirt with white print, shorts, and a light blue backpack.

Anyone with information is asked to call CrimeStoppers at 955-3800.