A search and rescue dog from Hawaii is the latest resource to help find two missing Saipan girls in a massive effort that has included a weeklong dig of a landfill.

The dog from the Hawaii State Civil Defense Urban Search and Rescue Canine unit is to join the search this week, FBI Special Agent Tom Simon said Monday via phone from Saipan.

Simon is among 10 agents from Hawaii helping with the search for Faloma Luhk, 10, and her sister Maleina Luhk, 9. The girls were reported missing by their grandparents when they didn’t come home May 25. They were last seen waiting for their school bus but never made it to Kagman Elementary.

The FBI and local authorities of the U.S. Commonwealth of the Northern Mariana Islands spent seven days digging through 30,000 cubic feet of the island’s trash, which yielded no leads, Simon said. They were looking for human remains or the girls’ backpacks. Hundreds of backpacks were found, including four Dora the Explorer bags similar to one worn by one of the girls.

“None of us were looking forward to the idea of finding human remains,” Simon said, adding that gives hope the girls can be found alive. “It’s encouraging us to search even harder.”

Authorities have found the girls’ disappearance baffling because Saipan is known to be a small, close-knit community.

Local residents have joined the search and the FBI is offering a $10,000 cash reward for information leading to the girls. Streets are lined with posters bearing the girls’ faces.

“I’ve never seen such a unified effort to recover missing children before in all of my years as a FBI agent,” Simon said.

For the FBI to get involved, there has to be reasonable belief the case is a kidnapping.

“As time marches on, it becomes clearer and clearer they were most likely abducted by someone as opposed to running away from home,” Simon said.