Update 5:29 p.m. EDT: Here's video of thick clouds of smoke rising from the site of the derailment (WARNING: Contains graphic language):

Update 5:06 p.m. EDT: The truck driver injured in the derailment was listed in serious but stable condition at Maryland Shock Trauma Hospital, Baltimore County Executive Kevin Kamenetz told a news conference. There were no indications of any other injuries.

Two nearby warehouses were damaged from the explosion, Kamenetz said. He added that the air is safe in the area around the derailment and explosion.

"There is no evidence of any toxic inhalants," he said. "Our fire department folks have not ordered any evacuation." As a precaution, residents living within 20 blocks of the incident were told to "stay out of the area," according to Kamenetz.

Chief John Hohman of the Baltimore County Fire Department said the two cars burning contained fluoride and chemicals used in making plastic and polyester coatings. Hohman said the chemicals are considered hazardous but not toxic (toxic chemicals would prompt an evacuation.) He said officials are concerned about whether they should extinguish the fire or "let it free-burn," which he said may be the safest way to contain the incident.

Update 5:02 p.m. EDT: Two of the cars are still on fire, according to WBAL.

Update 4:48 p.m. EDT: The chemicals on board the train are not considered toxic, according to fire officials on the scene.

Update 4:44 p.m. EDT: The truck driver has been identified as the person hospitalized. Two CSX employees were on the train and were uninjured.

Update 4:28 p.m. EDT: Fifteen CSX train cars were involved in the derailment, according to the Baltimore County Public Safety Twitter account. Residents within 20 blocks of the incident are being ordered to evacuate. One person was hospitalized due to "shock trauma."

Original post: A freight train derailed and exploded Tuesday afternoon in Rosedale, Md., near Baltimore, resulting in collapsed buildings and sending a thick plume of smoke and chemicals into the atmosphere.

Hazmat crews responded to the scene where the CSX train derailed in Rosedale around 2:20 p.m. Tuesday after colliding with a truck, according to WBAL, causing an explosion.

The Baltimore County Public Safety Twitter account said preliminary reports indicated that several buildings collapsed around the site of the Rosedale derailment. There were no reports of injuries, however.

The cause of the train derailment is unclear as of Tuesday afternoon. A resident who was near the derailment described hearing the explosion.

"We are in the Hamilton area and just felt a huge rumble,” Linda Stelmack told WBAL.

Twitter user @KRL224 posted the following photos of the flames on his account: