After a security breach, Apria Healthcare is offering 11,000 affected patients free credit monitoring.

The California-based healthcare company says 4,178 patients in Arizona were affected, including 1,100 in Southern Arizona.

The company offers home healthcare services and products, including home oxygen therapy, sleep apnea equipment, home medical equipment and enteral nutrition.

Today, Apria announced that the breach occurred in June, when an employee’s laptop was stolen from a locked vehicle in Phoenix. The employee managed billing functions for the company and the laptop contained information about Apria patients in California, Arizona, New Mexico and Nevada, officials said.

Apria says it is sending notices to all impacted patients, and offering them a complimentary subscription to a credit monitoring service in order to monitor for potential impact on their credit.

The files on the stolen laptop’s hard drive contained patient information, including Social Security numbers and names, and possibly birth date and other personal or health information.

“There has been no indication that any information has been accessed or misused,” Doreen R. Bellucci, Apria’s associate general counsel and privacy officer, said in a prepared statement. “However, Apria has nevertheless taken many steps necessary to address the incident and is committed to fully protecting all of our patients’ personal information.”

Bellucci said the company is notifying federal and state regulatory agencies about the incident. She said the company is also in the process of encrypting its laptops and strengthening other aspects of its internal patient privacy security program.