Shots have been fired at the motorcade of Pakistani Prime Minister Yousuf Raza Gilani, although it is not clear if he was in the convoy at the time.
Interior ministry officials said the car was on its way to collect Mr Gilani from Islamabad's airport.
Earlier, his press secretary told the BBC that unidentified gunman fired on Mr Gilani's car as he was travelling from the airport into the city.
It is not clear who carried out the attack, which is being investigated.
Mr Gilani's government is grappling with a growing threat from Islamist militants.
http://news.bbc.co.uk/2/hi/south_asia/7595572.stm