June 13 (Reuters) - All major Gulf stock markets dropped on Thursday after suspected attacks on tankers in the Gulf of Oman, with a missile strike by Yemen's Houthi rebels on a civilian airport in southern Saudi Arabia also weighing on risk sentiment.
Two tankers were hit in the suspected attacks and their crews were evacuated, shipping sources said. Four tankers in the region were struck in a similar incident a month ago.
On Wednesday, Houthi rebels carried out a missile attack on a civilian airport in southern Saudi which wounded 26 people. The Saudi-led military coalition in Yemen said it would respond forcefully.
Saudi's share index declined 0.8%, snapping five days of straight gains, with heavyweight petrochemical maker Saudi Basic Industries decreasing 2.3% and Al Rajhi Bank losing 0.8%.
The index has gained over 15% year-to-date, outperforming its major Gulf peers in a rally led by foreign investors.
A third tranche of the FTSE Russell emerging market index will kick in this month after Saudi stocks were included in two tranches in March and April.
The Abu Dhabi index dropped 0.7% with First Abu Dhabi Bank sliding 1.1% and Aldar Properties retreating 2.1%.
Qatar's index eased 0.6% as Industries Qatar dropped 1.6% and Qatar Fuel shed 1.1%.
In Dubai, the index decreased 1% with 22 of its stocks declining and one rising. Emaar Properties shed 1.1%, while Emirates NBD lost 0.9%.
($1 = 3.6728 UAE dirham) (Reporting by Ateeq Shariff in Bengaluru; editing by John Stonestreet)