RIGA, Latvia (AP) -- Tug boats were struggling Monday to free a stranded cruise ship with nearly 1,000 people on board, and the head of the coast guard recommended the ship be evacuated.
The Mona Lisa ran aground on a sandbank off the coast of Latvia.
The Bahamas-registered Mona Lisa was on its way from Kiel, Germany, to Riga when it ran aground Sunday on a sand bank about 17 kilometers (10 miles) from the Latvian coast.
Coast guard officials said the ship was not damaged and the passengers, mostly Germans, were safe and not at risk.
Three tug boats tried unsuccessfully to pull the ship off the sand bank Sunday, and a fourth tug boat was added as the rescue operation resumed early Monday, officials said.
Rescuers also pumped out the ship's fuel to make it lighter, but were still unable to free the vessel, officials said.
Coast Guard Service head Hermanis Cernovs told The Associated Press that he had recommended that the 984 people aboard the Mona Lisa be evacuated, but added that the final decision was up to the captain.
Passengers still have full use of the liner's onboard facilities, including access to fresh water, officials said.
The cause of the accident was being investigated. However, weather was not a factor, coast guard spokeswoman Liene Ulbina said Sunday.
The ship has a crew of 237, including three U.S. citizens. The captain is a Greek national, she said.