The head of Iran's judiciary, Ayatollah Mohammed Yazdi, has set up a special judicial commission to investigate the recent killings of a number of writers and opposition figures.

Ayatollah Yazdi said the decision had been taken to improve coordination of information and evidence relating to the cases.

Following the murders, several committees were set up by the police and thesecurity services to track down the killers.

Since then several people have been arrested.

But Iranian moderates, who suspect hardliners within Iran's conservative establishment of being behind the killings, are sceptical about the announcement.