The bodies of three US soldiers, missing for six days, have been found in a muddy swamp near the Lithuanian city of Pabradė, where they were taking part in military drills, the US Army has confirmed.

Rescue teams are still searching for a fourth soldier.

"The soldiers we have lost in this tragedy were not just soldiers - they were a part of our family... But the search isn't finished until everyone is home", said Maj Gen Christopher Norrie in a statement issued by US Army Europe and Africa.

The complex search and rescue mission has included the US Army and Navy, plus Lithuanian and Polish Armed Forces in an effort that has required "tremendous resources", the statement said.

The four soldiers went missing on the morning of 25 March while carrying out an exercise in their M88A2 Hercules - a large armoured vehicle that is designed to recover damaged tanks and other vehicles from battlefields.

They were "conducting a mission to repair and tow an immobilised tactical vehicle" when they went missing, the statement said.

The soldiers' vehicle was found submerged in a bog near the border with Belarus early on 26 March. Pulling it out of the mud was a difficult mission.

US Navy divers were brought in to hook cables onto the sunken vehicle, and had to manoeuvre "through thick layers of mud, clay, and sediment with zero visibility", the statement said.

Those cables were then connected to another two M88A2 Hercules, which also started to slide into the bog, leading to several bulldozers being called on.

Other heavy construction equipment including excavators and sluice and slurry pumps were brought in, as well as technical experts and "several hundred tons of gravel and earth", the US Army said.

On Sunday, soldiers, military commanders and Lithuania's defence minister attended a mass that was held in the capital city, Vilnius.

"Lithuania mourns together with the American nation," the country's President Gitanas Nausėda wrote on X.

"Please accept my heartfelt condolences, as well as those of the Lithuanian people, to you, the loved ones of those who lost their lives, and all the people of the United States of America," he said, addressing US President Donald Trump.

Lithuania, a Nato and EU member, is the base for more than 1,000 American troops stationed on rotation.

The identities of the four soldiers, who were assigned to the 1st Armoured Brigade Combat Team, 3rd Infantry Division, have been withheld until their next of kin are informed.

They had been deployed to Lithuania as part of Operation Atlantic Resolve - a response to Russia's invasion of Ukraine. Their home base is Fort Stewart, in the US state of Georgia.

The US Army and Lithuanian authorities are investigating the cause of the accident.