Sana’a - Yemeni security officials say two car bombs targeting security checkpoints killed at least nine soldiers in the southern city of Mukalla, which was recently recaptured from al-Qaeda.The first attack on Monday was carried out by a suicide car bomber who rammed his vehicle into a checkpoint, killing at least nine soldiers. The officials had no immediate details about the second attack.The officials spoke on condition of anonymity because they were not authorised to speak to the press. No group has claimed responsibility for the attacks.Al-Qaeda's Yemen affiliate ruled Mukalla for a year until the militants withdrew in April. The city has seen a number of suicide attacks in recent weeks, most carried out by an Islamic State affiliate. The two jihadi groups are fierce rivals, divided over leadership and ideology.