As changes in Yemen develop rapidly this week, the situation is raising questions about security, loyalty and what's coming next. But one thing seems clear: Saudi Arabia and the United Arab Emirates (UAE) are determined to guarantee their interests in the exploited, proxy-war-torn country.

Yemen's Southern Transitional Council (STC) continued to gain victories this week, seizing many government and military sites in Zinjibar, Abyan province. This comes after the separatist group staged a successful military coup Aug. 10 in Aden, the internationally recognized government's temporary capital.

On another front, a US Reaper drone was shot down south of Houthi territory in Yemen, US officials said Wednesday, though it was unclear immediately who was responsible or what country was operating the device. Some reports said Washington was blaming Iran, which the United States accuses of supporting the Houthis; others simply said the incident was still being investigated.

Also Wednesday, a delegation headed by STC president Aidaroos al-Zubaidi arrived in Jeddah, Saudi Arabia, to take part in Saudi-sponsored talks with the recognized Yemeni government. The coup split what had been an alliance between the Saudi-backed government of President Abed Rabbo Mansour Hadi and the UAE-supported STC against Houthi rebels. The rebels ousted Hadi's government in 2014.