German MPs of Turkish origin have been warned not to travel to Turkey and will get increased police protection after Germany's parliament declared the 1915 massacre of Armenians a "genocide", according to media reports.

Eleven MPs have been getting threats after the resolution, which has injected fresh tensions between Germany and Turkey, was passed in the beginning of June, the reports say.

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Der Spiegel, a German news magazine, said the foreign ministry had warned the MPs against travelling to Turkey because their safety could not be guaranteed.

"It is unspeakable to know that it is not possible to fly there for now," Aydan Ozoguz, Germany's integration commissioner, was quoted by Der Spiegel as saying.

Other MPs with Turkish roots have also cancelled business trips to the country, it said.

Separately, the Frankfurt Allgemeine Sonntagszeitung reported that the 11 MPs will now receive increased police protection and further security measures for both their professional and private activities.

"The threats against MPs of Turkish origin are unacceptable," Thomas de Maiziere, Germany's interior minister, told the paper. "Of course security measures will be adjusted if necessary."

He stressed, however, that the majority of the 3.5 million people with Turkish roots who live in Germany were "good neighbours" and said the perpetrators were "isolated cases".

'Death threats and insults'

Cem Ozdemir, the leader of Germany's Green Party, who initiated the resolution, told Turkey's Armenian weekly Agos that despite receiving "death threats and insults", at least they were "not imprisoned" and not had their "immunity lifted for having simply expressed what we thought, unlike our colleagues in Turkey".

Ozdemir told the Allgemeine Sonntagszeitung that he had received threats, reading: "At some point, your German friends will have forgotten that - we won't" and "We will find you everywhere."

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He also called on Turkish groups in Germany to condemn the death threats.

Turkish President Recep Tayyip Erdogan has said that MPs of Turkish origin who voted for the resolution should be given blood tests, and has accused them of having "tainted blood" and of being terrorists.

On Thursday Norbert Lammert, the president of the Bundestag, said threats against individual MPs were attacks on the entire parliament.

Millions of Germans have Turkish heritage following a wave of so-called guest worker immigration during Germany's economic boom of the 1960s and 70s.

Source: Agencies