Police in Upper Austria on Monday said they had arrested four Germans who were laying white roses in memory of Adolf Hitler at the house where the Nazi dictator was born.

The group was visiting the border town of Braunau am Inn on the afternoon of April 20 — Hitler's birthday. 

What did the police say?

Police arrested two sisters, 24 and 26 years old, as well as their 29- and 31-year-old partners.

The group had been laying flowers on a window ledge at the house. One of the women was spotted by police giving a Hitler salute as the two couples posed for photos.

The woman said the gesture had been intended as a joke and that she did not mean it seriously. However, police who inspected her phone found Nazi-themed chat messages and pictures being shared between the four.

Police said they were reporting all four to prosecutors on suspicion of breaking an Austrian law that prohibits the symbols of Nazism.

Police patrols are stepped up on April 20 each year, with special attention paid to the house in Braunau am Inn. Hitler lived at the house until he was three years old, when his family moved to the nearby Bavarian city of Passau. 

Work started to remodel the building in October, with the renovation intended to prevent neo-Nazis from visiting the site on the border with Bavaria.

The state-owned building is to be used as a police station and for human rights training.

rc/wmr (dpa, AP)