LIVERMORE (CBS 5 / AP) — An apartment explosion that left two people in critical condition on Saturday night was connected to illegal drug activity, but evidence suggests the burned unit was not a methamphetamine lab, a police lieutenant said Monday.

Livermore residents Evan Aviles, 21, and his girlfriend Lexie Huston, 22, and their friend Paul Lom, 34, of San Jose, were still in critical condition Monday, Livermore police Lt. Mike Peretti said.

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They were taken to hospitals in San Francisco, Santa Clara and Sacramento with severe burns after an apartment at 3624 Silver Oaks Way burst into flames around 5:15 p.m. Saturday, Peretti said.

He said illegal drug paraphernalia was found in the apartment and was likely a factor in the fire, but the apartment wasn’t a meth lab.

“There is no evidence to suggest that,” he said.

Neighbors in the area have returned to their homes after an evacuation on Saturday, Peretti said. The explosion did not affect the air quality or any surrounding structures.

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Livermore resident Mike Anderson, 25, lives a block away from the explosion site on Silver Oaks Way.

He said he was on his way home when the explosion happened, but that neighbors in the area told him it was loud and made their walls shake.

Moments after the explosion was contained, Anderson was just outside the area, observing.

“You could smell chemicals and by-products of the smoke,” he said.

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