The Mount Baldy resort and popular nearby areas were ‘temporarily closed’ on Monday and would remain that way until further notice, authorities said.

The actor has now been missing for four weeks, after being reported missing in the Mount Baldy region of the San Gabriel mountains on January 13.

Two weeks have now passed since Sands was first reported missing on January 13, with numerous searches on foot and from the air having taken place.

Authorities said they were ‘hopeful’ the special device would be able to more accurately pinpoint an area on which to focus efforts.