DUBAI: Bahrain sounded its missile alert sirens for a second time Monday as Iran retaliated over US airstrikes targeting it.
The warning urged the public to seek shelter in the island kingdom, home to the US Navy's 5th Fleet.
There was no immediate word on any damage or casualties in the attacks Monday morning.
Earlier, missile alert sirens had sounded at dawn on Monday.
The US military earlier said it wrapped up its latest round of attacks targeting Iran after hitting dozen of targets.
Iran's paramilitary Revolutionary Guard said it was in the process of launching attacks in response.
Iranian attacks on Sunday stretched Bahrain, Kuwait, Qatar, Jordan and even Oman - whose territorial waters with Iran make up the strait. The narrow mouth of the Persian Gulf, which once saw a fifth of all oil and natural gas pass through it, has become the key issue challenging an interim deal between the US and Iran.
Iran and the US are nearly at the midway point of the 60-day period of that deal, which was supposed to set up talks for a permanent end to the war. Instead, it has devolved into a series of attacks over the strait and its future, worrying world leaders the Iran war could resume.
"A return to full-scale hostilities would have catastrophic consequences," United Nations Secretary-General Antonio Guterres said in a statement.