GRIFFIN, Ind. – A worker at a southwestern Indiana pig operation was in critical condition after falling into a pit filled with hog manure.

Griffin Fire Chief Tim Compton told the Evansville Courier & Press (http://bit.ly/VTZvsC) that an employee of Griffin Pig fell into an 8-foot-deep pit that is used to hold manure. The manure produces methane gas, which is highly explosive and can cause asphyxiation.

Compton said the fall occurred about 8 a.m. The worker was in the pit for about 45 minutes before another employee noticed and flagged down a Wadesville firefighter.

The firefighter used a rope to lower himself into the pit and rescue the man.

The worker was flown by helicopter to an Evansville hospital. Compton did not release his name.