Nine wooden stakes and pieces of a head pig have been found in a piece of land where a mosque is scheduled to be built in Germany, police said.

According to DPA news agency, the stakes were planted on the plot of land in the east German city of Erfurt.

The Islamophobic incident occurred after numerous protests were held against the proposed place of worship.

Police said they are not aware who planted the stakes and the pig parts, adding that an investigation has been launched regarding the incident.

There have been a number of demonstrations against the Ahmadiyya mosque, including erecting large Christian crosses on a neighboring piece of land.

Pigs are considered unclean by Muslims and are constantly being used in anti-Islam protests across the West.

Using parts of pig’s carcass is considered highly offensive for Muslims, who do not consume pork.

A number of pig heads were also found last month, hanging on a fence outside the Moroccan ambassador’s residence near Paris.

Earlier in May, a pig’s head was also found outside the office of German Chancellor Angela Merkel. It came after Merkel face strong opposition to her immigration policies which allowed over 1.1 million people, mainly Muslim refugees, into the country.