Authorities in Texas were forced to shut one of the busiest waterways in the US Gulf Tuesday after a bulker collided with a chemical carrier in heavy fog.

The US Coast Guard says the Houston Ship Channel will be “partially closed indefinitely” following an incident involving ADM Shipping’s 52,000-dwt Harvest Sun (built 2001) and US Shipping Corp’s 48,800-dwt tankerCharleston (built 1983).

“We had a minor collision and there's an area we're asking ships to refrain from passing through," a spokesman said.

No injuries or pollution were reported and both vessels are believed to be anchored safely outside the channel where they are preparing for inspections.

According to local media reports, four ships are waiting to enter the waterway, which serves the Port of Houston and a large cluster of petrochemical refineries.

Officials say the Harvest Sun, which is flagged in the Marshall Islands and controlled by the shipping arm of US agricultural giant Archer Daniels Midland, was traveling South from Houston to Texas City when the incident began to unfold at around 9:00 am local time.

The US-flagged chemical carrier, one of seven units in a fleet linked to an owner that changed its name from US Shipping Partners after emerging from bankruptcy in 2009, was transporting a cargo of chemical acetone in a Northbound voyage to Houston.

Both ships maintain insurance coverage with the UK P&I Club, according to data from Equasis.