JEFFERSON CITY, Mo. (AP) — A house exploded early Saturday in Missouri's capital city, injuring six people, including three critically, fire officials said.

The explosion happened at 2:44 a.m., according to a statement from the Jefferson City Fire Department. The cause of the explosion was under investigation.

The home was so damaged that it took more than three hours for the fire department's Special Operations Rescue Team to reach all the victims in the debris, the statement said.

Three of the home's occupants were listed in critical condition, and three were in stable condition.

Two pets also were rescued from the home, the department said.