Earlier this week, a similar incident occurred in the Persian Gulf. “The fact that this happened two days after their failed attempt in the Arabian (Persian) Gulf seems to be an escalation,” the official said. The incident began on Thursday, the official said, when the Iranian Navy ship was seen pulling two US drones out of the water “in an attempt to steal them,” according to the official. The US then quickly moved in with two nearby destroyers, USS Nitze and USS Delbert D. Black, as well as two helicopters and radioed to demand the return of the drones. The Iranians agreed but asked to wait until daylight on Friday for security reasons to which the US agreed, the official said. The unmanned sea vessels, known as Saildrone Explorers, were operating in international waters in the southern Red Sea, four miles away from the nearest maritime traffic lane, according to the US Central Command. The unarmed drones had been operating in the area for more than 200 days without incident, the Central Command said, and were taking unclassified photos of the environment. Iranian state television broadcast video showing the drones being pushed back into the water from the deck of the Iranian warship. Iran’s state television reported that the Iranian navy seized the drones while conducting an anti-terrorist mission in the Red Sea. “The destroyer Jamaran seized two ships on Thursday to prevent any possible accident…the two ships were released after international shipping lanes were secured and a warning was issued to the US fleet,” state television said. The episodes come at a sensitive time as negotiations for a revived nuclear deal appear to be faltering. On Thursday, the US State Department said Tehran’s latest response to the European Union’s proposal to revive the deal was “not constructive”. The US official noted that unprofessional interactions with the Islamic Republic of Iran Navy are rare. When other unprofessional incidents have occurred, they have usually involved Iranian Revolutionary Guard Corps (IRGC) ships rather than the regular Iranian navy. IRGC ships and small craft have had multiple unprofessional interactions with the US Navy in recent years. Earlier this week, the US Navy prevented an Iranian ship from intercepting a US maritime drone in the Persian Gulf in what a senior US commander called an “egregious” and “unjustified” incident. While US forces in the region were crossing international waters on Monday, they saw an Islamic Revolutionary Guard Corps Navy support ship, the Shahid Baziar, towing a US-operated maritime drone, also known as a Saildrone unmanned surface vessel. Explorer. A U.S. Navy coastal patrol vessel, the USS Thunderbolt, “was operating nearby and responded immediately,” the Navy said. After the Iranians attached a line to the marine drone, US forces in the area contacted the Iranians directly to say they wanted the drone back, and the Iranians eventually disconnected the tow line. The US is increasingly using commercially available leased drones for maritime surveillance. The official said that because it involves commercial technology, there is currently no concern that Iran has gained access to classified technology.