A boat carrying mostly American tourists on a sightseeing trip down the Danube River (search) rammed a landmark bridge Thursday, injuring 19 people, authorities said.

The MS Viking Europe tour boat, registered in Germany, struck a piling on the Reichsbruecke bridge (search), one of the main spans carrying traffic over the Danube in central Vienna, officials said.

A total of 135 passengers were aboard, 129 of them Americans, authorities said. The rest were Britons and Canadians, and the boat was manned by a crew of 39. The vessel began its journey in Amsterdam, Netherlands, and its final destination was Budapest, Hungary.

Police Col. Robert Haas said the 19 victims, all of whom were U.S. or British citizens, suffered minor injuries, mainly scratches and bruises. One of the injured was a cook who suffered light burns, Haas said.

The injured were treated at a hospital, rescue officials said.

The collision damaged the restaurant deck of the boat, which was packed with tourists enjoying the scenery on a bright, sunny morning.

The Vienna navigation authority said the stern of the boat rammed the bridge at about 8 a.m. as it was beginning to turn around, smashing windows and showering passengers with shards of glass.

The boat had begun the Vienna leg of its journey in the quaint Danube town of Duernstein, about 50 miles west of Vienna, and was preparing to swing around to return to the river's main branch when it struck the bridge, Haas said.

The Reichsbruecke bridge, a popular landmark in Vienna often photographed for its dozens of ornate lamps, was not seriously damaged, officials said.

Michael Kaindl, a Vienna city engineer, told Austrian media the skipper should have waited until the boat was downstream of the bridge to begin the turn. The boat was just upstream of the span when it hit, officials said.

Investigators said the second officer, and not the boat's captain, was at the helm when the accident occurred. The officer was said to be distressed and in shock and was being treated by psychiatric experts.

The German company that operated the boat, Klaus Saar GmbH (search), said it was sending a technical expert to evaluate the damage and determine if the boat could continue to Budapest. The vessel was built in 2001, the company said.

Dozens of tour boats ply the Danube daily, carrying thousands of tourists through the Austrian capital. Serious accidents are relatively uncommon. The worst recent accident happened in 1996, when a Slovak tour boat foundered in floodwaters and sank, killing eight Slovak tourists.