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Russian police have been raiding Turkish companies in different regions of Russia and, in some cases, have suspended their operations, two Turkish businessmen with investments in the country have told Al Jazeera.
Moscow has also started sending back Turkish trucks loaded with exports at the border and stopped Turkish tourists - who normally do not need visas - entering the country, at least two businessmen said.
Turkish and Russian foreign ministries, contacted by phone, had not replied to Al Jazeera's questions at the time of the publication of this story.
Moscow's move comes after Turkish fighter jets shot down a Russian Sukhoi Su-24 warplane on Tuesday for allegedly violating Turkish airspace.
The two sides, who are at odds over the Syrian crisis, have opposite claims over whether the airspace breach is true or not.
"Turkish companies in Russia, particularly construction companies, are being raided," a Turkish executive with a manufacturing company active in Russia told Al Jazeera, on condition of anonymity.
"They check if anyone with expired or no working visas is actively working in these companies or not. They check if working regulations were implemented or not.
"There have been serious breaches in this area within construction companies and Russian authorities know it. Activities of some companies have been frozen on these grounds."
Cevdet Seylan, a businessman with trade relations in the city of Kazan, also confirmed that police had been raiding Turkish companies there.
Trucks returned
Osman Bagdatlioglu, the chairman of Turkey's Ornamental Plants and Products Exporters Union, said that several trucks loaded with flowers returned back to Turkey on Wednesday after Russian authorities blocked their entry into the country.
"Six trucks came back yesterday. We stopped all deliveries. We stopped deliveries by planes as well," Bagdatlioglu told Al Jazeera.
"Officially there are no obstacles, but we come across unofficial ones. This will have a massive impact on our commercial segment in short and middle terms. In Europe, one of our largest partners is Russia," he said.
The goods blockage was also reported by Adnan Dalgakiran, a member of the Turkish Exporters Assembly, who tweeted on Wednesday evening: "Entry of Turkish goods has been blocked at Russia customs."
Another businessman, who wished to remain anonymous, said that all trucks suspected of carrying Turkish products are asked to wait at the border, regardless of their license plate.
"At the border, they check every single truck, whatever license plate it carries. They check everything about the product," he said.
"They count the products, check their weight, etc, and find an excuse to make them wait or send them back."
Meanwhile, several Turkish citizens confirmed to Al Jazeera that Russia was sending back Turkish tourists trying to enter the country by finding "excuses" and was delaying entry of Turks with work or residence permit.
Turkish and Russian tourists have been able to travel between the two countries without a visa since 2011, following an agreement signed between the two countries.
Wait at customs
Seylan, the businessman, said that Russian authorities made him and other Turkish nationals wait at Kazan's airport for an hour while entering the country on Wednesday.
"Police went to our residence addresses, checked our information and then we were allowed to go into the country," Seylan told Al Jazeera.
"On [the evening of] November 24, there have also been raids on Turkish residences and cafes that Turks go to.
"Students and professionals were detained. They were released after being questioned."
Turkish Airlines officials told Al Jazeera that Turkish authorities did not warn the company about any restrictions over using Russian air space. The state-owned carrier added flights continued as normal.
Russian authorities had hinted at new commercial measures against Turkey following the downing of the country's warplane.
Russia carried out its first air strikes in Syria on September 30, saying the Islamic State in Iraq and the Levant (ISIL) and "other terrorist groups" were the targets.
Turkey has long been campaigning for the ousting of Syrian President Bashar al-Assad and has joined other countries in criticising Russia's air campaign, saying the strikes are mainly hitting rebel groups opposed to Assad rather than ISIL.
Turkey had warned Russia over violations of its airspace multiple times before Tuesday's downing by Turkish air forces, Ankara says.
On photo 1: Protesters hurled eggs and stones at the Turkish embassy in Moscow, a day after Turkey shot down a Russian warplane [AP]
Photo 2: On Thursday, dozens of Turkish trucks were unable to enter Russia via Georgia and drove back to Turkey. (Photo: Cihan)