Anadarko Petroleum Corp. (NYSE: APC) said April 26 it will shut in more than 3,000 vertical wells across the northeast Colorado counties where it operates following an explosion and fire that killed two people in a recently built home located within 170 ft of a well that drilled in 1993 and later acquired by Anadarko.

The announcement was part of a statement released by the company regarding an explosion and fire in Firestone, Colo. that occurred on April 17.

State regulators are still investigating the cause of the explosion, and Anadarko said in its statement that the company has been working cooperatively with fire officials and state regulatory agencies in their investigations since the time of the accident.

“While the well in the vicinity is one aspect of the investigation, this is a complex investigation and the origin and cause of the fire have not been determined,” Frederick-Firestone Fire Protection District Chief Theodore Poszywak recently told The Denver Post.

He said his department is continuing to gather and analyze evidence to determine the cause of the explosion.

He also said that surrounding homes were not in danger.

"This terrible tragedy has left all of us with heavy hearts, and the families and their loved ones are in our thoughts and prayers," said Al Walker, Anadarko chairman, president and CEO. "Words cannot express how saddened we are that this occurred in a community where many of our employees, their families, and friends live and work. We share the community's gratitude for the courageous response of neighbors and nearby construction crews who quickly came to the aid of the family, as well as the first responders and others who made sure surrounding homes were kept safe."

The company operates more than 3,000 producing vertical wells of the same vintage. The wells will remain shut in until the company's field personnel can conduct additional inspections and testing of the associated equipment, such as facilities and underground lines associated with each wellhead.

Particular focus is being placed on areas where housing and commercial developments are occurring in close proximity to existing infrastructure.

Anadarko said the wells will not be restarted until each has undergone and passed these additional inspections. The company currently anticipates the process will take two to four weeks, depending on weather. The wells currently account for total production of about 13,000 net barrels of oil equivalent per day.

"Our teams will remain actively engaged with residents in the Firestone community," said Brad Holly, Anadarko’s senior vice president, U.S. onshore exploration and production, said in the statement. "Colorado residents must feel safe in their own homes, and I want to be clear that we are committed to understanding all that we can about this tragedy as we work with each investigating agency until causes can be determined."