One person has been arrested in Iran after a home-made bomb was thrown at President Mahmoud Ahmadinejad's convoy.

Mr Ahmadinejad was unharmed by the attack, which took place during a visit to the western city of Hamadan.

The source said Ahmadinejad's convoy was targeted as he was travelling from Hamadan's airport to give a speech in a local sports arena. The president was unhurt but others had been injured in the blast.

Ahmadinejad, who has cracked down on opposition since a disputed June 2009 presidential election, appeared on live Iranian television at the sports stadium. He looked unperturbed and made no mention of any assault.

The populist, hardline Ahmadinejad has accumulated enemies in conservative and reformist circles in the Islamic Republic as well as abroad.

Al Arabiya television said an attacker had thrown a bomb at Ahmadinejad's convoy before being detained. Dubai-based Al Arabiya cited its own sources as saying the bomb had hit a car carrying journalists and presidential staff. There was no immediate claim of responsibility.