LISBON, (Reuters) – Authorities delayed a rescue operation Wednesday for a vessel that was laden with luxurious cars and had been burning for a week at sea.

Teams were not able to board Felicity Ace so heavy tug boats spray water onboard to cool down the vessel. It is carrying about 4,000 vehicles (including Porsches, Audis, Bentleys).

On Wednesday morning, 22 firefighters were called to evacuate the scene.

Port officials said that some of these vehicles were electric, and the lithium-ion battery power has made it very hard to put out the flames.

João Mendes Cabeças, the captain of the nearest port on the Azorean island of Faial, said the blaze had lost its intensity, probably because there was little left to burn.

The navy stated that salvage teams were planning to board the vessel, located 170km southwest of Azores in Portugal, to evaluate its condition and prepare it for towing.

The vessel may be town to Europe or the Bahamas, but it is not clear.

Cabeças told Reuters bad weather prevented the team from boarding the ship. According to the Portuguese weather agency IPMA, waves as high as 2.5m battered Faial’s coast on Wednesday.

The salvage team was expected to be flown to the ship on a helicopter belonging to the Portuguese air force, which will decide on Thursday if the operation can proceed, Cabeças said.

Ship manager Mitsui O.S.K. Lines Ltd. (MOL) stated that on Tuesday, the vessel was still in flames but stable and no oil spillage had been reported. It didn’t respond to a Reuters inquiry about the causes of the fire.

Experts in insurance estimate that the incident could lead to losses up to $155 million.