The UAE on Monday strongly condemned renewed Iranian strikes targeting civilian sites and facilities in the Emirates, saying they represented a "dangerous escalation" and a direct threat to security and stability.
The country's air defences detected four cruise missiles launched by Iran, in the first attacks on the country in weeks.
The Ministry of Defence said three of the missiles were intercepted "over the country's territorial waters, while the fourth fell into the sea".
Three people were injured in a fire at Fujairah Oil Industry Zone after a drone attack from Iran. They were all Indian citizens and were taken to hospital for treatment, the Fujairah Media Office said in a statement.
The UAE's Ministry of Foreign Affairs said the air strikes were an "unacceptable transgression" and were in violation of the principles of international law and the United Nations Charter.
The ministry said the UAE would not compromise on protecting its security, sovereignty and its people under any circumstances and it reserved its full and legitimate right to respond to the attacks.
The UAE said it held Iran fully responsible for what it described as treacherous attacks and emphasised the need for an immediate halt to hostilities.
Flightradar 24 - an online account tracking global air travel movements - said flights bound for Dubai and Sharjah were in a holding pattern.
UAE authorities on Monday issued a series of missile alerts in Dubai, Sharjah and Abu Dhabi, urging residents to seek shelter.
The Ministry of Interior and the National Emergency Crisis and Disaster Management Authority said the country was responding to missile threats in a series of messages sent out from 5pm onwards.
"Air defense systems are currently responding to a missile threat. Please remain in a safe location and follow official channels for warnings and updates," Ncema said.
It marks the first time such alerts have been issued since the early hours of a conditional ceasefire agreed between the US and Iran on April 8.
The Emirates faced a daily barrage of missile and drone strikes from Iran following the outbreak of the war on February 28.
The renewed attacks follow the start of a US operation to allow commercial vessels stranded in the Gulf by the Iran war to start passing through the Strait of Hormuz under US military protection.
There were reports of attacks on several vessels in the area on Monday, including a ship affiliated with Abu Dhabi National Oil Company (Adnoc) as it transited through the strait.
Two drones targeted the ship but no injuries were reported, the UAE's Foreign Ministry said.
The Ministry accused Iran of a "terrorist attack" and expressed its "utmost condemnation and denunciation", calling it a flagrant violation of UN Security Council Resolution 2817 on freedom of maritime navigation.
"Targeting commercial navigation and using the Strait of Hormuz as a tool of pressure or economic blackmail constitutes acts of piracy by the Iranian Revolutionary Guard [Corps] and poses a direct threat to the stability of the region and its people and to global energy security," it said.
The UAE called on Iran to stop the "treacherous attacks" and commit to reopening the strait unconditionally.
Meanwhile, the UK Maritime Trade Operations said it had received a report of an incident involving a cargo vessel about 36 nautical miles north of Dubai.
In an advisory, UKMTO said the vessel reported a fire in its engine room, with the cause not immediately known.
All crew were reported safe and accounted for, it added, noting that authorities are investigating the incident.
