Iran launched an attack targeting US navy ships on Monday, but the US military has not yet acknowledged the incident, the Wall Street Journal reported, citing US officials. The reported attack came after Iran fired ballistic missiles at a US aircraft carrier and a guided-missile destroyer over the weekend.No US navy ships were hit in the attacks, according to the officials.However, the repeated attempts to target American warships have raised concerns that Iran may be using more advanced weapons and could be receiving help from China or Russia.The attacks also show that Iran is taking a more aggressive approach as a US blockade of Iranian ports puts further pressure on its economy. The moves could increase tensions, as the US has warned it will respond to attacks on its navy vessels.After Iran tried to target a US aircraft carrier over the weekend, the US struck three Iranian oil tankers. Washington said the tankers were helping fund Iran’s military and proxy groups. US officials said the strikes were intended to make clear that attacks on American warships would not be tolerated.Iranian state media has claimed that the country is using new missiles with advanced technology to target US warships. According to weapons analysts, these missiles could be equipped with electro-optical seekers, allowing them to use images to adjust their path toward moving targets.However, Iran would still need to know roughly where US warships are located before launching an attack. This has raised concerns among US officials that China or Russia could be helping Iran track American naval vessels.Iran unveiled the Qassem Bassir, a medium-range ballistic missile equipped with such seeker technology, last year, according to John Caves, a senior research associate at the Wisconsin Project on Nuclear Arms Control. He said other Iranian missiles, including the Khalij Fars, also use the technology.The US hopes its blockade and sanctions will put enough pressure on Iran to force its leadership to back down. So far, however, Iran has refused to do so and has increased its threats against US navy vessels.A US navy official said 19 warships are currently supporting operations in the Middle East.