TEHRAN, May 25 (Xinhua) -- Air defenses on Iran's Qeshm Island, strategically located near the Strait of Hormuz, were activated Monday, with the cause still unknown, Iran's semi-official Mehr News Agency reported, citing local residents.

Meanwhile, Iran's semi-official Fars news agency reported that Iranian forces downed a "hostile drone" in the past few hours over the strategic waters of the Gulf with a newly-unveiled air defense system. ■