LAWRENCE (CBS) – A Lawrence store clerk locked a knife-wielding thief in her shop as he tried to escape, and then called police.

Robber with a knife inside Lawrence liquor store.

“Please hurry because he has a knife and I’m here by myself,” the clerk says on the 911 call. “He’s trying to break the door to get out because I locked him in here.”

At one point, the thief was heard on the call begging the female clerk to let him out.

Police eventually arrived and found 19-year-old Dennis Washington hiding in the basement.

The store owner, Anthony Silva, says he has never seen anything quite like it, and is glad his employee did not get hurt.

“It’s not advisable to lock someone in after you’ve been robbed,” says Silva. “It’s just not a safe way to go. I told her if it ever happened again just let him go, it’s not worth it.”

The clerk told WBZ’s Jim Smith that she locked him in the store because she really didn’t see him as a threat.