Eight medical centre employees were kidnapped in northwest Nigeria on Sunday, police said, although local sources said more people had been taken.
A large number of unidentified armed men attacked Kaduna state's Saye Tuberculosis and Leprosy Health Centre at around 1500 GMT, after a "heavy exchange of fire" with officers, local police spokesman Mohammed Jalige said."Eight people were kidnapped," he said, adding they were presumably taken for ransom.
Local sources said 15 people had been abducted, including two nurses and their baby.
They said the large number of attackers had forced officers to flee.
"The truth is that the police abandoned their station after violent exchanges of fire," a Saye resident told AFP.
"The attack on the police station was a distraction whilst another group attacked the dormitories of the health centre workers," another neighbour said.
Criminal groups, known as "bandits" by the authorities, terrorise parts of the northwest and centre of Nigeria.
They attack villages, steal cattle and kidnap people for ransom.
They operate from camps in the Rugu forest, which sprawls across Zamfara, Katsina, and Kaduna state in Nigeria, as well as Niger.
Most are motivated by material gain, although some have sworn allegiance to militant organisations in northeast Nigeria, hundreds of kilometres away.
Recently there has been a spate of attacks by such groups against schools and universities, with mass abductions of students for ransom.