Tajikistan has strained relations with the Taliban in Afghanistan and several border clashes have broken out in recent months.

The foreign ministry said a drone and firearm attack hit workers of a Chinese company in the country's south.

"The attack, carried out with firearms and a drone loaded with grenades, claimed the lives of three employees of Chinese nationality," it said in a statement.

Dushanbe rarely comments officially on such incidents, and it did not say who it suspects carried out the attack.

Militants from jihadist groups are active in the mountainous border region, which spans around 1,350 kilometres (840 miles) between the two countries.

Muslim-majority Tajikistan, one of the poorest countries in the former Soviet Union, has been concerned about possible flare-ups in extremism since the Taliban returned to power in 2021.

President Emomali Rakhmon, in power since 1992, is openly critical of the Taliban, and urged the group to respect the rights of ethnic Tajiks, estimated to make up around a quarter of Afghanistan's 40-million population.

At the same time, Tajikistan has cautiously engaged in some areas, including through diplomatic meetings, the opening of markets in border towns and supplying electricity.

Tajikistan's foreign ministry said Thursday, "criminal groups located in the neighbouring country (Afghanistan) continue to commit acts aimed at destabilising the situation in the border regions."

Several Chinese companies operate in Tajikistan, particularly in mining and natural resources, often located in the mountainous border areas.

One Chinese worker was killed last year in a similar attack near the Afghan border.