BBC News, Tehran
Mrs Ebadi told police one recent note said that her death was near
Iran's President Mahmoud Ahmadinejad has ordered police to ensure the safety of Nobel Peace Prize laureate Shirin Ebadi, state media reports.
The move comes a day after Mrs Ebadi said that death threats against herself and her family had intensified.
The president also ordered a police investigation into the threats Mrs Ebadi had received, reports IRNA.
Shirin Ebadi, who is a lawyer, won the Nobel Peace Prize in 2003 for her work on human rights and democracy.
She has continued to speak out on human rights issues in Iran and has defended clients in a number of high profile rights cases.
During media interviews in the past Mrs Ebadi has spoken about death threats made against her.
In a letter to Iran's police chief, distributed to the media on Monday, she said that threats against herself and her family had intensified.
She said a note had recently been left at the entrance of her office building saying that her death was near.
And she enclosed what she said were copies of other threatening letters she had received.
The Nobel Laureate said those who wished her dead did not have any personal animosity towards her - they were just against her thoughts and beliefs.
Therefore, she suggested, it should not be difficult to find those who had written such threatening notes.