Mohammad Saleh Khazali, the son of Iranian political activist Mehdi Khazali, says his father’s health has deteriorated so severely in prison that he has been transferred to hospital.

On his Facebook page, the son of the jailed activist reports that his father is currently at Imam Khomeini Hospital in Tehran.

Mehdi Khazali was arrested recently, following a number of other arrests since the 2009 election protests, and he began a hunger strike as soon as he was arrested.

Khazali is reportedly refusing both food and drink. The reports indicate he might even have had a heart attack.

Khazali’s recent arrest was reported on opposition websites in late May in Mazandaran Province.