(CNN)-- The United Kingdom Maritime Trade Operations (UKMTO) said Tuesday that an oil tanker reported being hit by a missile while transiting the Strait of Hormuz on the southern route off the Omani coast.

The center clarified that authorities received the first report of the missile attack on Monday, noting that the incident occurred 13 nautical miles (about 15 miles) southeast of the city of Lima in Oman and remains under investigation.

The UK Maritime Trade Operations had announced Monday that another oil tanker reported being hit by an unknown projectile 40 nautical miles (about 46 miles) northeast of Qalhat in Oman.

It added: "Ships are advised to transit with caution and report any suspicious activity to the UK Maritime Trade Operations."

These reports come amid rising tensions in this vital waterway, through which roughly one-fifth of the world's oil and liquefied natural gas supplies typically pass. Tehran announced overnight that it targeted what it described as "two renegade supertankers," claiming they ignored warnings issued by Iranian authorities.