Militants in Yemen fired on Saudi coalition troops in Saudi Arabia 's Asir region , citing outlet reports . militants have taken Yemen 's presidential palace in Aden , sources unknown . U.S. forces are patrolling off Yemen in search of suspicious shipping , a U.S. defense spokesman says .
Militants in Yemen fired on Saudi border troops in Saudi Arabia 's Asir region , media outlet says . Rebels have taken Yemen 's presidential palace in Aden , sources say . U.S. warships are patrolling off Yemen in search of suspicious shipping , a U.S. defense official says .