Virtually the entire high command of Columbia's most active leftist guerrilla group has been killed or captured in a sweeping military operation near the border with Ecuador, officials reported yesterday.

The Army commander, Gen. Fernando Landazabal, told reporters that 75 members of the April 19 Movement, known as M19, were captured and 16 killed in clashes that also left government soldiers dead in southern Columbia.

Interior Minister German Zea said the prisoners included Carlos Toledo Plata, a former leftist congressman and founder of the guerrilla group, and Rosemberg Pabon, who led the two-month occupation of the Dominican Republic Embassy in Bogota last year.

Unconfirmed press reports said guerrillas killed in action may have included another top M19 leader, Ivan Marino Ospina, and Carmen Cordona, the woman who acted as M19 negotiator during the embassy siege.

A hard-line dissident faction of the M19 killed American Bible translator Chester Bitterman March 7, 48 days after kidnaping him in Bogota. The main leadership of the movement has denied any responsibility for the crime.

Neither the Army commander nor the interior minister gave a full account of the army operations that followed an M19 raid last week on the town of Mocoa in Putumayo Territory near the Ecuadoran border.