Image copyright Facebook Image caption Canadian Ece Heper is being held in Turkey

A Canadian dual national has reportedly been detained in Turkey for allegedly insulting the country's president.

Ece Heper, 50, was arrested on 30 December in the north-eastern town of Kars, her lawyer Sertac Celikkaleli told The Canadian Press.

Canadian officials say they are offering consular assistance, but released no further information.

Turkey's penal code states that anybody who insults the president can face up to four years in prison.

Ms Heper's friend Emrah Bayram told the BBC she was arrested for Facebook posts critical of President Recep Tayyip Erdogan.

"It's ridiculous, she's expressing her opinion," he said.

Image copyright AFP Image caption President Erdogan's opponents criticised the arrest, saying he had created "an environment of fear"

Friends say Ms Heper, who lived in Ontario and is reportedly a Canadian-Turkish citizen, has "some health issues" and they are worried about her access to medication while in detention.

Along with her lawyer, they fear it could be at least a month before her case goes to trial. They have contacted human rights organisations over her case.

Mr Erdogan has been accused of mounting a growing crackdown on freedom of speech.

Almost 2,000 cases for insulting Mr Erdogan have been opened in recent years.

They include a former Miss Turkey and a 16-year-old student.

Another man was found guilty of insulting the president and given a suspended one-year jail sentence after he shared images comparing Mr Erdogan to the fictional character Gollum.