(NewsNation) — The family of missing Texas A&M student Caleb Harris tells “NewsNation Now” they’re remaining hopeful for his safe return as the search enters its third week.

“We’re intensifying working with the authorities, they’re doing everything they possibly can and getting additional help,” said Caleb’s father Randy Harris. “We’ve got a lot of volunteers out searching as well in different areas. We’re beginning to get some leads, but so far nothing’s panned out.”

Caleb was last seen in the early hours of March 4. He had walked his dog before 3 a.m., which wasn’t unusual for him, according to his father. He returned home with the dog, then left again and has not been seen since. His father said his phone has been dead.

“His phone just went offline, whether it was turned off or ran out of battery,” Randy said.

Randy previously told NewsNation’s Chris Cuomo that his son has no medical conditions or mental health issues that might have contributed to his disappearance, and he doesn’t have a habit of leaving without letting people know where he was going. Harris described his son as a normal 21-year-old man who loves to fish and hunt.

Randy said there’s much about Caleb’s disappearance that doesn’t fit with his personality.

“He was a very scheduled individual. He was texting me photos of fishing lures earlier in the evening of what he was planning on using the next day,” said Randy. “Everything was looking good, He had good grades. There’s no indication of anything. He left his wallet and his keys. We’re 100% sure he was barefooted, even.”

Randy said the family has leaned on their faith to stay positive.

“We just have to depend on our faith and our family and the sheer incredible amount of people that have helped us,” said Randy. “The volunteers that are out there still today doing different searches all over Corpus Christi.”

Caleb Harris has brown hair and eyes, stands 5’11” and weighs around 180 pounds. Anyone with information is urged to call the Corpus Christi Police Department at 361-886-2840 or 361-886-2600.

NewsNation’s Stephanie Whiteside contributed to this report.