About 600 Afghan servicemen who crossed the border into Tajikistan while retreating from Taliban militants have been flown home on four flights since late on July 6.

A source in Tajikistan’s law enforcement told Radio Liberty’s Tajik Service that the last flight carrying 130 Afghan servicemen left the Kulob airport on the morning of July 7.

Tajik authorities have not said how many Afghan servicemen remain in Tajikistan.

Kulob airport officials said they were not authorized to comment on the transfer of Afghan forces.

A Tajik security source told Reuters that some 300 more soldiers are set to return in the coming days.

Hundreds of Afghan soldiers crossed into Tajikistan amid Taliban advances in northern Afghanistan as U.S.-led international forces have withdrawn from Afghanistan ahead of a self-imposed September 11 deadline.

A doctor told RFE/RL’s Tajik Service that at least three Afghan soldiers seriously injured in the fighting in Afghanistan remain in a hospital in the Jaihun district of Tajikistan.

Meanwhile, a source in the Defense Ministry said a group of Russian military advisers have arrived from Russia to Tajikistan and are inspecting the situation at the Tajik-Afghan border.

The developments in northern Afghanistan have worried bordering states, including Tajikistan, which has said it is mobilizing 20,000 men to reinforce its border.

Tajik authorities have said they are preparing for a possible influx of refugees.