Iran says it is targeting American forces and bases across the region.
President Donald Trump announced "major combat operations" against Iran on Feb. 28, with massive joint U.S.-Israeli strikes targeting military, government and infrastructure sites.
Delegations from the U.S. and Iran entered negotiations in June aimed at a war-ending deal based on a memorandum of understanding signed by both countries.
The U.S. and Iran have nonetheless continued to exchange strikes, with the strategic Strait of Hormuz the primary flashpoint.
Bahrain's Interior Ministry said that air raid sirens were activated in the kingdom on Wednesday.
Saudi Arabia's Civil Defense body also issued an alert warning in the eastern city of Dammam, which sits along the Persian Gulf, "to warn of a danger." The alert was lifted around 10 minutes later.
There were 13 crossings of the Strait of Hormuz on July 20 and nine on July 21, according to maritime intelligence company Kpler.
Addressing the new threats from the Houthis in the Bab el-Mandab Strait -- which sits at the southern end of the Red Sea -- Kpler said that "traffic declined sharply across both chokepoints on 21 July, with Strait of Hormuz crossings down 31% day-on-day to nine vessels and Bab el-Mandeb down 34% to 29."
Attacks in the Strait of Hormuz are "reinforcing concerns that uncertainty across both regional chokepoints could reshape routing decisions, increase freight costs and sustain higher geopolitical risk premiums for energy markets," Kpler said.
-ABC News' Victoria Beaule
Air defenses in Jordan downed eight of 10 projectiles fired by Iran on Wednesday, according to statements from the Jordanian Armed Forces.
Iran fired six missiles and four drones into Jordanian territory according to the statements. Eight of the projectiles were intercepted. Two Iranian missiles fell in remote areas.
No injuries or damage were reported, the military said.
-ABC News' Ghazi Balkiz and Othon Leyva
Iran's military claimed on Wednesday to have launched a wave of drone strikes targeting U.S. Army ammunition storage and logistical sites at Camp Doha in western Kuwait, in a statement carried by the semi-official Tasnim News Agency.
