The historic Wilhelmina Tower in the Dutch city of Valkenburg has collapsed under unknown circumstances and a search has been launched for possible victims, the city government said.

The 30-meter-high tower was a popular tourist attraction. Valkenburg Mayor Daan Prevoo said the collapse happened in the morning when the tower area was inaccessible, so authorities do not expect any casualties.

Built in 1906, the tower had a restaurant and offered visitors the opportunity to climb to the top.

The cause of the collapse will be investigated, the regional civil protection agency said, adding that it was not yet known if there were any casualties.

The city has urged tourists not to visit the collapsed building and the area has been cordoned off, reports say. KosovaPress.