Iran’s opposition movement has told euronews they have been unable to contact one of their leaders, Mehdi Karroubi, for over a week.
Karroubi and his wife are said to be under house arrest in Tehran.
The opposition say a number of government officials visited their apartment late on Monday night.
One of Karroubi’s advisors, Mojtaba Vahedi, spoke to euronews by telephone from Washington DC, where he lives in exile.
“Yesterday afternoon, some 30 people from the Information Ministry, certainly in coordination with the security and justice departments, came into the building where his office and apartment are,” Vahedi said.
“They were very unruly and shouted insults. Eyewitnesses who were there told me that they were the same people who had been outside Mr Karroubi’s place, chanting offensive slogans.”
The opposition are also waiting for news on Karroubi’s two sons. His youngest, Ali, has been arrested by the authorities.
His other son, Hussein, is said to have escaped arrest as he was not at home when officers came by to seize him.
Another key opposition figure, Hossein Mousavi, has also been under house arrest with his wife since February 14th.
He led the so-called Green Movement protests in 2009 after Iran’s disputed presidential election in June of that year.