Supporters of opposition leader Nawaz Sharif were attacked by gunmen near the Pakistani capital on Thursday. Four people were killed and three others were injured in the worst violence in the campaign for January 8 elections.

Former Prime Minister Sharif accused the government supporters for the attack which occurred near the city of Rawalpindi.

Sharif said: "Some Q League workers fired at our people," Reuters quotes.

Sharif’s supporters were at a rally just 10 miles from the airport when the incident happened and Sharif was at a mile from the shooting.

Sadiq ul-Farooq, a spokesman for Sharif's party, said: “Nawaz Sharif and his procession are safe, but we have received reports that a few people were wounded and maybe a few suffered fatal injuries,” Guardian Unlimited reports.

The people who got injured were from Sharif's Pakistan Muslim League-N group.

Four people were killed and other three were wounded, according to Local police Chief Mohammed Hussain.

Imtiaz Ranjha, a spokesman or the ruling Pakistan Muslim League-Q party, accused the Sharif's supporters for the attack saying that it was provoked by them.

Just a few miles from the incident, in Rawalpindi police was preparing for the first campaign rally of Benazir Bhutto since she came back in the country.

Bhutto wanted to hold an earlier rally, but President Pervez Musharraf forced her to cancel it due to security issues.

People had to go through metal detectors on Thursday before they’ve entered the public park which was decorated with colors of Bhutto’s party: red, black and green. Also massive portraits of her decorated the park.

Almost 140 people were killed in October when a suicide bomber hit a welcoming parade for Bhutto in Karachi city.