At about 1:00 am on the 19 September a force of around 200 rebel troops, loyal to Augusto César Sandino, attacked the small garrison of Telpaneca under the command of Marine First Lieutenant Herbert S. Keimling.

Keimling's garrison included twenty men of the 5th Marines and a force of twenty-five Nicaraguan National Guardsmen.

The first sound of the fight occurred when a rebel soldier tossed an improvised explosive at the marine barracks but it exploded without hurting anyone and only served to alert the sleeping garrison.

The rebels then charged the barracks under cover of fog but were beaten back by accurate fire.

At that point the battle was a skirmish in which both sides engaged at a further range until about 2:30 am when the fog began to lift.