The chief of the Los Angeles Police Department said that the burglars, who stole tens of millions of dollars from an armored truck depot in Sylmar during an Easter Sunday break-in, accessed the interior of the building through the roof before they entered the vault.
“It’s unclear how they accessed the vault itself inside the building. There were no obvious signs of entry into the vault,” said LAPD Chief Dominic Choi, raising questions about whether the vault was unlocked or someone involved with the break-in knew how to open it.
Source: Sylmar cash burglars slipped into vault, left little evidence – NBC Los Angeles