An international rights group says Lebanese authorities have detained a Palestinian human rights activist.

Human Rights Watch says Ghassan Abdallah, director of the Palestinian Human Rights Organization, was detained after being summoned to the General Security Directorate early Monday and was held incommunicado for more than 24 hours.

It quoted his lawyer as saying that Abdallah has since been transferred to Military Intelligence. It says Abdallah was able to make a telephone call and has access to medication. It says authorities have not clarified the basis of his detention or allowed him to speak with his lawyer.

Lebanese officials could not immediately be reached for comment.

It was not immediately clear if his detention was linked to the Palestinians' mass protests in Gaza.