At least eight people were also abducted from the National Tuberculosis and Leprosy Centre in Zaria early on Sunday morning.
Two nurses and a 12-month-old child were among those seized, said a hospital worker.
There has been a recent spate of abductions from schools and universities for ransom.
On Monday, reports emerged of another mass kidnapping from a school near Kaduna city, about 80km (50 miles) south-west of Zaria.
