Traditional police work made way for exacting science yesterday at the site of Monday's station wagon explosion near the Middlesex Shopping Center.
The scattered remains of the blown-apart white Taurus wagon were hauled to a county police facility for further examination, but not before federal and Baltimore County bomb experts searched through each piece -- trying to separate vehicle particles from bomb remnants.
Such evidence, it is hoped, will determine what kind of ingredients were used to make the explosive that killed the vehicle's five occupants, authorities said.
Police initially thought that slurry, a water-based blasting agent that looks like oatmeal in some forms, was the cause of the blast. But other theories point to two other high-grade explosives -- Astrolite and Kinepak, liquid explosives used by construction and mining firms.
Through a spokesman, county police were officially saying last night that slurry was the main component of the bomb, but federal investigators said physical evidence pointed in another direction.
"Slurry has nothing to do with this investigation," said Cliff Lund Sr., explosives enforcement officer for the federal Bureau of Alcohol, Tobacco and Firearms. "We don't know for sure what kind of explosive was used yet, but we do know that any type of high explosive could do that type of damage. We're checking into a number of them."
Mr. Lund said there was a large amount of the explosive used, set off by some type of detonator, but he could not be more specific.
Both explosives are binary. Ingredients are sold in separate containers, and cannot explode until they are combined.
Astrolite explosives are fluid, and can be pumped into tubes, sprayed, poured into containers, soaked into the ground or squirted into cracks. It was developed as a result of rocket research, but is now used mostly for commercial purposes.
According to explosives experts, Kinepak is also a liquid and, like Astrolite, has the potential for high-shock energy, or shattering ability. Used mostly in construction and mining, Kinepak, which also comes in a version called Kine-stick, can also be used to clear trails.
Mr. Lund said both types of explosives have to be purchased from licensed dealers. Buyers must fill out a form to obtain any high-grade explosives, he said.
Kinepak and Astrolite are available only to the blasting industry and "you have to have a federal and state approval to buy, store, haul and use" those two explosives, said Al Grieger, vice president of Explosives Experts Inc. in Sparks.