NEU-ULM, Germany (AP) _ Floodwaters from the Danube River burst small dams and flooded basements in southern Germany today, as thousands of people worked to evacuate residents and fill sandbags.

Brackish waters swamped two floors of a hospital in Neu-Ulm, on the Danube about 85 miles west of Munich, forcing officials to evacuate 99 patients Sunday in all-terrain trucks.

A prison also was threatened, and authorities transferred 80 inmates to a facility in Memmingen farther south.

Severe rains late last week swelled Alpine rivers, cutting off entire towns at higher elevations. Lake Constance, nestled in the Alps where Germany, Switzerland and Austria meet, reached its highest level in 200 years, but officials said no emergency threatened there.

At least five people in Germany, Switzerland and Austria have been killed in the flooding. A teen-ager who disappeared after his inflatable boat overturned remained missing.

Disaster alarms remained in place today in seven cities, including Neu-Ulm and Ingolstadt. More than 10,000 people worked around the clock to help evacuate residents and erect sandbags against the rising waters.

The flooding was most severe along the Danube: A dam burst in Neustadt, authorities warned that saturated dams in Ingolstadt were on the verge of breaking and the situation between Donauwoerth and Regensburg was reportedly critical. Floods were expected to reach Passau, near the Czech border, on Tuesday.

In Neu-Ulm, river patrols were picking up residents who wanted to retreat to dry ground.

``But they have to call from the windows or use a mobile phone,'' patrol officer Kai Huster said. ``The phones aren't working anymore.''

Salvatore Marino waded barefoot through knee-deep water with his two children to get to his brother's home, where he planned to spend the night.

While the Marinos fled the rising waters, gawkers gathered at a riverside promenade near the city's center, packing cafes, filling streets and making it difficult for emergency vehicles to pass.

``This disaster tourism is crazy!'' said Wieland Pokorny, chief police inspector. ``They've come here from all over.''