VILNIUS – A U.S. armored vehicle that went missing in Lithuania has been retrieved from a swamp after a six-day search but there is still no information about the fate of the four American soldiers who were on board, Lithuanian officials said Monday.

“The armored vehicle was pulled ashore at 4:40 a.m., the towing operation is complete, Lithuanian Military Police and US investigators continue their work,” Defense Minister Dovilė Šakalienė said Monday morning in a post on Facebook.

The soldiers were on a training exercise at the massive General Silvestras Žukauskas training ground in the town of Pabradė when they and their vehicle were reported missing in the early hours of Tuesday morning, the U.S. army said.

“Until the investigators have more details, we need to stay calm and focused, and keep in mind the sensitivity of the situation and the concerns of the soldiers’ families,” Šakalienė posted on Facebook.

She made clear to reporters that the first information about fate of the soldiers will be delivered by the U.S. army.

The soldiers, all from 1st Brigade, 3rd Infantry Division, were conducting tactical training when they went missing.

Hundreds of Lithuanian and U.S. soldiers and rescuers took part in the search through the thick forests and swampy terrain around Pabradė, which lies just 10 kilometers (6 miles) west of the border with Belarus. The M88 Hercules armored vehicle was discovered on Wedneday submerged in 4.5 meters (15 feet) of water.

A large-scale recovery operation got underway but “water, thick mud and soft ground around the site have complicated recovery efforts and have required specialized equipment to drain water from the side and stabilize the ground” in order to pull the 70-ton vehicle ashore, the army said.