November 23, 2006 2:40 PM

PODGORICA, Montenegro-A massive landslide in Montenegro's Tara River Canyon has clogged the waterway and caused flooding in Montenegro, prompting authorities to begin evacuating villagers late Thursday.

The landslide earlier Thursday in the central county of Mojkovac, about 90 kilometers (60 miles) northeast of the capital, Podgorica, created a natural dam of mud, earth and collapsed trees that completely cut off the flow of the Tara River, police said.

"The sight is horrible. Tara is no longer flowing," Zoran Begovic, the police officer in charge of emergencies, told Montenegrin state television.

Police began evacuating residents from the nearby village of Slatina after another village, Kaludra, was flooded. Part of the regional motorway has been closed. No one was reported hurt.

Police did not know what caused the landslide, but Begovic said that an "entire hill had collapsed into the river."

Rescue services will try Friday to clear the river basin of the debris, which was piled 150 meters (164 yards) wide and 90 meters (98 yards) deep.

The river was expected eventually to rise enough to flow over the dam, but Begovic would not give predictions when that was expected. Material damage was significant, he said.

The Tara River Canyon is part of a U.N. world heritage site.

It came into media focus last year, when Montenegrin environmentalists forced the government to abandoned plans to build a dam that would flood the canyon, Europe's deepest, famous for its unspoiled beauty, trout fishing and whitewater rafting.