AlQa'dah 2, 1433, Sep 18, 2012, SPA -- The death toll from a friendly fire incident involving the South Sudanese military has risen to 27 while 10 soldiers are still missing, dpa quoted an army spokesman as saying on Tuesday. On Saturday South Sudanese troops opened fire on a boat carrying 170 fellow soldiers in the remote Lul area, killing 10 soldiers instantly. Philip Aguer, an army spokesman, told dpa that the soldiers on the boat disobeyed orders and should not have been on the river after dark. "These soldiers did not adhere to the standing orders," Aguer told dpa. The young nation has witnessed several incidents of lethal friendly fire in recent years.