There has been a surge of migrant workers leaving Russia for Tajikistan after the 22 March concert hall attack, according to Tajikistan's ministry of labour, migration and employment.
"We receive a lot of calls. These are most likely not complaints about harassment, but fear of our citizens, panic, many want to leave," Shakhnoza Nodiri, deputy head of the ministry, was quoted by Russian state news agency TASS as saying.
"We are now monitoring the situation, we have more people coming (to Tajikistan) than leaving."
Gunmen opened fire with automatic weapons at concert-goers over a week ago in the worst attack in Russia in two decades, leaving at least 144 people dead.
Four of the suspected gunmen are Tajik citizens and were arrested along with seven other suspects.
