Updated at 6:05 a.m.

Two Americans are among four foreign cyclists killed over the weekend in the Central Asian country of Tajikistan when a car swerved to hit them and then assailants jumped out of the vehicle and stabbed the victims. The Tajik government accused a banned Islamist party of being behind the attack, and the Islamic State also claimed responsibility.

The U.S. Embassy in Tajikistan confirmed the attack, which occurred in Danghara district, about 60 miles southeast of the capital, Dushanbe. The New York Times describes the area as "a picturesque mountain road that has been popular with Western bicyclists for its dramatic and remote scenery in a region close to the border with Afghanistan."

The other two cyclists killed in the attack were from Switzerland and the Netherlands, officials said. None of the four were immediately identified. Three others in the same group survived the attack, including one with a knife wound, officials said.

"According to multiple sources, on July 29, Tajik citizens hit seven foreign cyclists with their vehicle, exited the car, and stabbed the cyclists with knives," the U.S. Embassy said in a statement on its website, adding it had "no evidence that indicates a heightened level of threat to U.S. citizens."

The Associated Press reports, "Interior Minister Ramazon Rahimzoda told reporters that one of the survivors had knife wounds and police found knives and guns with some of the suspects. He described the car crash as 'an attack,' and said investigators were examining all possibilities, including a road accident, murder and terrorism."

A purported video of the incident obtained by Radio Free Europe shows the blurry image of a car crossing a lane of traffic and then hitting something — apparently the cyclists — at the edge of the opposite lane.

In a statement on Tuesday, the Tajik Interior Ministry said it had detained four people linked to the attackers after reporting Monday that security forces had killed four suspected attackers and detained a fifth. However, the U.S. Embassy reported three killed and one detained.

The ministry, citing the confession of a surviving suspect, said the assailants had been trained in Iran and intended to flee to neighboring Afghanistan after Sunday's attack. It blamed the banned Islamic Renaissance Party of Tajikistan, which plotted a failed coup against the government in 2015, of being behind the attack.

However, the Islamic State on Monday issued a bulletin through its news agency describing the attackers as "soldiers of the Islamic State." In the past, ISIS has claimed responsibility for attacks that later turned out to be the work of groups or individuals unaffiliated with the terrorist network.

Tajik police say they found a vehicle that had damage consistent with a car-bicycle collision, which led them to the suspected assailants.

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