Karachi: A fresh wave of violence sparked by the killing of a senior PPP activist hit Pakistan's biggest city, claiming as many as 11 lives over the last 24 hours and leaving scores wounded in drive by shootings and indiscriminate aerial firing incidents.

Two incidents turned out to be flashpoints for the latest round of violence that began on Saturday.

A senior leader of the ruling Pakistan Peoples Party, who headed the workers union in the national airlines PIA, Aamir Shah, was gunned down with his friend in a drive by shooting incident in the troubled Gulistan-e-Jauhar area, sparking more violence.

Shortly afterwards, a protest rally taken out by the Kachi Aman (Peace) committee was fired upon by unidentified gunmen. At least seven people were wounded in the incident as people ran helter skelter for cover.

Angry supporters of the committee soon after blocked the main Mauripur road which serves as a main transit route for containers and heavy good trucks, setting tyres and shops on fire.

The violence spread following this and at least nine more deaths were reported from different areas of the city in late night shootings, including three people killed in another troubled area, Baldia town.

The Peoples Unity President, Aamir Shah, who had also served as a bodyguard to slain prime minister, Benazir Bhutto was shot dead with his friend, Mairaj Khalid Jagirani, by attackers on motorcycles who opened fire at his white Toyota Corolla near Kamran Chowrangi in Gulistan-e-Jauhar.

Witnesses said the men intercepted the car befor shooting Shah and Jagirani. Karachi chief of police Saud Mirza said the assailants probably targeted the men shortly after they finished filling up fuel near Kamran Chowrangi.

He said it was too early to say anything about the motive behind the attack as the investigation was underway and details were being gathered.

As the news of the incident spread, agitated PPP workers reached the hospital seeking the arrest of the people responsible.

Amir Shah's name was among the party's senior activists and he had served at many different posts in his 18 years with the party.

The fresh wave of violence began after two days of calm in the metropolis.

Last week, around 16 people were killed and 21 wounded in violence after the Mutthaida-e-Qaumi Movement party called for a strike to protest against remarks by senior minister of the Sindh cabinet, Zulfiqar Mirza, against the party leadership and the Urdu speaking population.

The situation only improved after Mirza apologised for his remarks in a video released on all television channels and was summoned to Islamabad for a dressing down by President Asif Ali Zardari.

The government had claimed it had dispatched 500 frontier corps paramilitary troops to the country's financial hub to assist the police and rangers but so far the FC personal are yet to be seen in the city.

Earlier in the month, around 100 people were killed and over 250 wounded in the city, in four days of severe violence and anarchy.

(Agencies)