A fire aboard the Hong Kong-flagged ASL Bauhinia on Tuesday was not linked to Houthi attacks, the Red Sea and Gulf of Aden Joint Maritime Information Center said on Wednesday.

Shipping companies expressed caution about using the shorter route between Asia and Europe that many ships have avoided for more than a year.

An official described the cargo aboard the ASL Bauhinia container ship as ‘dangerous’. The cause of the fire was not immediately clear.

U.S. ships are returning to the Red Sea following promises from Yemen’s Houthi rebels to abstain from attacks on American and British vessels. The pledge, which comes after more than a year of shipping traffic disruption on a major international trade route,

An explosion has struck a Hong Kong-flagged container ship traveling north through the Red Sea, sparking a major fire that forced its crew to abandon the vessel