Three American sailors were last seen April 4 near Mazatlán, Mexico—now, the U.S. Coast Guard is working alongside Mexico’s navy to search for them. Kerry O’Brien, Frank O’Brien and William Gross were aboard a 44-foot vessel en route to San Diego, with a planned stop in Cabo San Lucas April 6 that they never made it to. Despite search efforts, the three sailors have yet to be found. “Urgent marine information broadcasts have been issued over VHF radio requesting all mariners to keep a lookout for the missing persons and vessel,” the Coast Guard said in a statement.