Turkey's Foreign Ministry summoned Sunday the Swiss ambassador in Ankara over terrorist organization PKK sympathizers' Saturday rally targeting President Recep Tayyip Erdoğan in Bern.
A ministry official, who spoke on condition of anonymity due to restrictions on talking to media, said the ministry has reiterated its uneasiness to Ambassador Walter Haffner over the issue.
The ministry called the Swiss side to take the necessary judicial measures against this criminal act, the official added.
On Saturday, the ministry conveyed Turkey's reaction to the deputy chief of mission of Switzerland in Ankara because Haffner was out of the city.
Supporters of the terrorist PKK, DHKP-C, YPG took part in the rally in front of the Federal Parliament building, located in Parliament Square in Bern.
The Swiss police did not intervene against the banner, which had a photo of Erdoğan, a gun pointed to his head and said "Kill Erdoğan" on it.
The Swiss Green Party also supported the rally, which was attended by approximately 250 PKK supporters who shouted slogans against Turkey and Erdoğan.
During the rally, speakers called for a "No" vote on a Presidential referendum which will be held on 16 April in Turkey.
The constitutional changes have been discussed since Erdoğan was voted president in August 2014. The 18-article bill was passed by parliament in January, with 339 votes in favor -- nine more than needed to put the proposal to a referendum.
The reforms would hand wide-ranging executive powers to the president and the post of prime minister would be abolished. The president would also be allowed to retain ties to a political party.
Other changes would see the minimum age for parliamentary candidates reduced to 18 and the number of deputies rise to 600. Simultaneous parliamentary and presidential elections for a five-year term would be held in November 2019 under the new constitution.
The PKK -- listed as a terrorist organization by Turkey, the U.S. and the EU -- resumed its armed campaign against Turkey in July 2015 and since then has been responsible for the deaths of approximately 1,200 security personnel and civilians, including women and children.
