(Reuters) – Kyrgyzstan’s foreign ministry has urged citizens of the Central Asian nation to put off unnecessary travel to Russia after a deadly shooting that was blamed on migrants from the region.

The developments have increased existing anti-immigrant sentiment in Russia, especially towards migrant labourers from the predominantly Muslim countries of Central Asia.

A Kyrgyzstan-born man was remanded in pre-trial custody by a Russian court on Tuesday, accused of providing accommodation to the four suspected perpetrators, who are of Tajik origin. Those four and three others of Tajik origin suspected of complicity are also in pre-trial detention.

Islamic State has said it was responsible for the attack and has released video footage of the massacre, which killed 139 people and wounded 182. The group has not identified any of the attackers.

Videos and photographs circulated online appear to show the suspects being tortured. The Kremlin declined to comment on the matter and many Russian politicians heaped praise on the security officers involved in the detentions.

Hundreds of thousands of people from Tajikistan, Uzbekistan, and Kyrgyzstan work in Russia, and some have already said it has become tougher for them to do so. Some passengers, for example, refuse to board taxis with Tajik drivers.

In an advisory issued this week, the Kyrgyz foreign ministry urged citizens to visit Russia only if necessary and, if they do, to make sure they have all the required documents on them at all times and comply with lawful orders of Russian police.

(Reporting by Olzhas Auyezov; editing by Philippa Fletcher)