Activist Abdullah al-Reyami, who has reportedly been detained since Tuesday, "has been called in to explain certain issues which he considers important in the field of human rights," the official on Thursday said, requesting anonymity.
"Al-Reyami comes up with statements and commits acts that are in breach of law and regulations. Such statements are also incorrect and contradict the position of Omani citizens," the official added.
Forty-year-old al-Reyami, who does not have a long record as a human rights activist, became active in protesting the innocence of a group of 31 Islamists who were convicted of plotting to overthrow the government and for membership of a banned organisation.
These were latter pardoned by Oman's Sultan Qaboos in June.
An unemployed liberal poet, al-Reyami criticised the government of the Gulf state over the arrests, accusing it of restraining freedoms.
But the Omani official protested that al-Reyami's claims were unfounded.
"Oman is a state of law and institutions, not a state where freedoms are restrained," he said.
He claimed however that calling al-Reyami into police custody is a mere "reforming and enlightening measure", after which al-Reyami would be released.