A breach of B.C.’s PharmaNet prescription medication system has compromised enough information to commit identity theft against roughly 1,600 people, the province revealed Friday.

The Ministry of Health said an unauthorized person used a doctor’s PharmaNet account without the doctor’s knowledge to access patients’ names, birth dates, addresses, telephone numbers and personal health numbers earlier this year.

Medical histories of 34 people were also accessed in the breach, which took place between March 9 and June 19, but no fraudulent prescriptions were obtained.

No banking information was taken, but the government warned the perpetrator did access enough personal details to make identity theft a concern.

Affected patients are being contacted by letter starting Friday, and the ministry is urging them to keep a close eye on their bank accounts, credit cards and online services.

They will also be offered free credit protection services to safeguard their personal information, the province said.

Concerned patients can contact their local pharmacy and request a keyword be added to their PharmaNet profile. They can also ask Health Insurance BC for a Medical Service Plan Alert, which forces health workers to ask for a second piece of identification when the patient’s personal health number is used.

The Ministry of Health and B.C.’s Office of the Chief Information Officer are continuing to investigate the breach.