A fire broke out aboard the Marie Maersk off the coast of Liberia on Wednesday, with the crew still fighting to control the blaze a day later, according to Maersk.

“The crew of the Marie Maersk detected smoke coming from containers onboard the vessel en route from Rotterdam, The Netherlands to Tanjung Pelepas, Malaysia,” Maersk said in a statement.

The Danish shipping giant confirmed that the crew remains safe while attempting to bring the situation under control. Two firefighting tugboats reached the stricken vessel late Wednesday to provide assistance.

The Marie Maersk, a Triple-E class containership sailing under the Danish flag, measures 399 meters in length and 59 meters in width. The vessel entered service in 2013 as the fourth ship delivered in Maersk’s Triple-E class of ultra-large container vessels with a capacity of 18,000 TEUs.

Maritime tracking data shows the ship’s current status as “Restricted Maneuverability” as it drifts off Liberia while firefighting efforts continue.

Dutch company SMIT Salvage has reportedly dispatched two specialized firefighting tugboats to assist with the emergency. Another Maersk vessel is reportedly positioned nearby and ready to provide additional support if needed.

The Marie Maersk was deployed on the Gemini Cooperation’s Asia-Europe service at the time of the incident. No information has yet been released regarding the cause of the fire or the extent of potential damage to cargo and the vessel.

This incident comes as the latest in a series of container vessel fires that have plagued the shipping industry in recent years, highlighting ongoing concerns about fire safety aboard increasingly large container vessels.