A Danish ferry operator said 294 passengers were stranded after the engine broke down on one of its ships in the Baltic Sea.

The Lithuanian military had earlier reported that there was a fire on the vessel because of an explosion in the engine room.

The country's air force said it had sent a helicopter and two more were on standby if needed.

Ferry operator DFDS has since said the malfunction aboard the Regina Seaways produced smoke, which triggered the fire extinguishing system in the engine room.

 Image: Google Earth

No passengers or crew members have been injured, according to a statement.

DFDS said Tuesday that passengers were assembled at emergency points in preparation for a possible evacuation, but it was not necessary because the "situation is under control".

The statement said that the extent of the damage was not fully known.

DFDS added that the ferry will be towed to Klaipeda in Lithuania.