Militants in Yemen 's oil - rich southern delta region , they killed 6 soldiers . This came after military raided dozens of militants ' camps . Its attacks on oil facilities have taken a toll . Largest rebel group has targeted foreign oil companies since 2006 .
Militants in Yemen 's oil - rich southern delta region , they killed 6 soldiers . This came after military raided dozens of militants ' camps . Largest rebel group has targeted foreign oil companies since 2006 .