Safety board chair: ATF blocking plant blast probe

WACO, Texas - The head of a federal safety board says federal agents and the state fire marshal are blocking the board from investigating a deadly Central Texas fertilizer plant blast.

In a letter to a U.S. senator planning hearings into the West Fertilizer plant blast, the chairman of the U.S. Chemical Safety Board says the board's investigation of the blast has been blocked by the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives and the State Fire Marshal's Office. The Waco Tribune-Herald reports that the chairman asks U.S. Sen. Barbara Boxer to help the board obtain evidence controlled by the ATF.

The ATF special agent in charge of the investigation tells the Austin American-Statesman that a criminal investigation comes with "certain sensitivities," while the State Fire Marshal's Office tells the paper evidence needs to be protected for now so that law enforcement produces one "clear cut" report.

The April 17 blast killed 15 people and injured about 200 others.