Colombian soldiers patrol the streets after a strict quarantine was declared to stop the spread of COVID-19 in Bogota, Colombia on Monday. Photo: AFP

The Colombian army said nine soldiers were killed and six wounded after a military helicopter went down Tuesday in the country's southeast during an operation against guerrillas.

The Black Hawk helicopter went down with 17 people aboard on a stretch of the Inirida River, in the country's southeastern Guaviare jungle region.

"Unfortunately, we have found the bodies of nine of our personnel," a military spokesperson said on Twitter.

The military did not say if the helicopter crashed or was shot down. Neither did it say anything about the other two soldiers who had been aboard the helicopter.

President Ivan Duque lamented on Twitter what he described as "an accident," and said the soldiers aboard the helicopter were supporting "operations against illegals."

According to the army, the helicopter was supporting a military sweep against the Revolutionary Armed Forces of Colombia (FARC) dissidents - leftist guerrillas who refused to sign the peace deal their comrades reached with the government in 2016.

There are some 2,300 dissident guerrilla fighters, according to military intelligence estimates.

AFP