The search is on for a team of thieves who stole millions of dollars in merchandise and cash after they tunneled into a downtown Los Angeles jewelry store.

The owners of Love Jewels say they’re out millions of dollars following the intricate break-in over the weekend. They suspect the thieves took weeks to tunnel into their store, using the abandoned theater next door to do so.

“They probably went in there every night, slowly dug it until there was enough room for them to get in,” the store owner’s son, who wished to conceal his identity, told NBC4.

Love Jewel is a family-run shop, and the owners believe they’re at a loss of upwards of $20 million. Police would not confirm that figure but they said they are investigating the crime.

“In the gold business, you reinvest everything so all our money was what was in the safe,” the son said.

“They were able to disable the cameras, disable the alarm and they were able to get into both the safes,” the son said. “They probably had five, six hours in here.”

The owners believe it took the thieves hours to cut into their safe.