Dubai's bourse dropped sharply minutes after opening on Monday as shares in builder Arabtec plunged for a second day in a row.
Arabtec tumbled its 10 percent daily limit while the Dubai index dropped 3.9 percent. Developer Union Properties fell 8.1 percent and bourse operator Dubai Financial Market was down 6.1 percent.
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Shares in Arabtec, which dominates trading in the emirate, plunged on Sunday after Aabar Investments, a key shareholder, did not confirm a media report which said Aabar planned to raise its stake. In a brief statement, Aabar said it was considering its options towards Arabtec but did not elaborate.
Arabtec said on Monday morning that its board would meet on Thursday afternoon to review its second-quarter earnings statement and other reports and recommendations, but did not give any details.
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Abu Dhabi's bourse was also weak, edging down 0.7 percent in early trade. Top real estate developer Aldar Properties sank 8.0 percent.