EDGEWOOD, Md. (WJZ) — An Edgewood man whose home was leveled in an explosion on Monday failed to properly disconnect a gas range and then lit a candle, ultimately leading to the blast, the Office of the State Fire Marshal said Wednesday.

Investigators determined the owner of 2506 Thornberry Drive, Delbert L. Markley Jr., 67, tried to disconnect his gas range in anticipation of a new one being delivered on Monday. Afterward, he lit a candle.

READ MORE: Daily Forecast: A Journey Up The Thermometer Today

But the gas range was not properly disconnected, and the house filled with natural gas, the fire marshal’s office said.

“Natural gas and propane are treated with a substance that has a distinctive odor that smells like rotten eggs. If you can smell it in your home, go outside and call 911 immediately,” State Fire Marshal Brian S. Geraci said. “Don’t smoke or use any electrical appliances, even a light switch or thermostat, because any spark could lead to an explosion.”

Markley was in a rear bedroom during the initial explosion and suffered second- and third-degree burns and other injuries, the fire marshal’s office said.

Following the explosion, Markley was able to pull himself from the debris and was helped by bystanders until first responders arrived, the fire marshal’s office said.

Markley’s two dogs were in the house at the time of the explosion. One was rescued Monday night, but the other had to be euthanized Wednesday morning due to its injuries, the fire marshal’s office said.

READ MORE: If You Don't Know Where Your Onions Came From, Throw Them Away To Prevent Salmonella, CDC Says

The explosion damaged adjacent homes.

Neighbors told WJZ they heard a loud boom and felt their own houses shake.

“I ran outside and in my backyard, you could actually hear all the debris falling, people screaming ‘get out the house, get out of the house, get out of the house now!’” said Fred Farlow, who lives a street away.

Henry Schwartzman, who lives next door, said the explosion knocked him off his sofa.

He ran to get his wife.

“I see smoke, flames and fire just shooting up so we got out right away,” he said.

MORE NEWS: Man, Woman Injured In Northwest Baltimore Shooting

BGE officials said Monday that all of its own equipment showed no damage.

CBS Baltimore Staff