Authorities say the incident happened at the Conejo Check Cashing in the 2400 block of Hillcrest Drive in the community of Newbury Park at about 9 a.m. The suspect forced his way through the roof, which landed him in a secure area of the business.
The suspect confronted the clerk, who had been helping customers, and demanded money. The clerk was able to escape during the robbery and was not injured.
Authorities say the suspect got away with an undisclosed amount of money. A suspect description was not immediately available, and it was unclear if the business had surveillance cameras.
Anyone with information is urged to call the Thousand Oaks Police Department at (805) 494-8224.