The US-led Joint Maritime Information Center (JMIC) raised the maritime security threat level in the Strait of Hormuz on Saturday from moderate to substantial.

The advisory was issued by the United Kingdom Maritime Trade Operations (UKMTO). JMIC is a multinational naval advisory body, and UKMTO serves as one of its core information-sharing partners.

The threat level was raised following attacks on commercial vessels near the Strait of Hormuz, according to the advisory. The notice also warned mariners of the presence of mines in the area and said naval forces are expected to operate there as mine-clearing activities continue.

Shipping through the strait gradually resumed after the United States and Iran reached a memorandum of understanding, prompting JMIC on June 18 to lower the maritime threat level in nearby waters to moderate.

However, a container ship and an oil tanker were attacked in nearby waters on Thursday and Saturday, respectively.

The US Central Command said on Friday that US forces had struck Iranian targets in response to an attack on a commercial vessel near the Strait of Hormuz a day earlier.

Meanwhile, international shipping data showed that although the attacks have reduced traffic through the waterway, commercial vessels are still transiting the strait.

JMIC also said on Saturday that, to accommodate simultaneous inbound and outbound traffic, the southern shipping lane in the Strait of Hormuz, near the Omani side and supported by the US military, has been widened.

The Navy of Iran's Islamic Revolution Guard Corps on Thursday once again stressed that the only authorized routes for vessels' passage through the strait are those announced by Iranian authorities.