ANTONITO, Colo. -- A 13-year-old and 18-year-old were seriously injured Thursday afternoon when police said a pipe bomb they were working on exploded in the southern Colorado town of Antonito.

Police Chief Joe Taylor, Jr. told the Alamosa Valley Courier that the two were apparently using a hammer to pack gun powder into a pipe.

Conejos County Sheriff’s Sgt. Andres Casados said the pipe appeared to have been about 6 inches long and 3/4 inch in diameter.

The newspaper reported that the 18-year-old lost much of his right hand and the 13-year-old sustained a broken leg and loss of muscle mass as a result of the blast. A large piece of shrapnel from the pipe was removed from the younger boy's leg.

Police said the blast occurred in a bedroom of a home at 309 River St.

A private duty nurse who was tending to an older woman in the same home began first aid for the teenagers immediately after the blast.

Read more about this story in the Valley Courier.