German police say they're seeking a man who's launched a series of attacks on a giant cross near the Austrian border.

The suspect is said to have attempted to cut down the cross on various occasions.

The large wooden symbol is placed on the summit of the Schafreuter mountain which on the border between Germany and Austria. The cross was first attacked in May, then in July and again recently.

The latest attempt was spotted by a helicopter pilot who was flying over the mountain.

Police say they are unsure of the motive behind the attacks but have not ruled out the possibility that they are religiously motivated. 

A German news outlet reported that the suspect police are seeking is "thought to be a man in his mid-thirties, around 1.80 metres tall, and fairly strong... with witnesses saying he had a foreign sounding accent".

If the motive for the attacks on the cross does turn out to be anti-Christian or anti-religious, it will join a long list of attacks on momuments to faith.

Iconoclasm is recorded in the Old Testament and throughout church history and remains an issue in parts of the world.