Pakistani police say they have killed five suspected anti-government fighters linked to a Taliban leader in the city of Karachi.

The police chief said the gunfight took place after officers raided an apartment in the west of the city on Saturday.

The armed men were loyal to Baitullah Mehsud, the Pakistani Taliban leader, and were planning attacks, Waseem Ahmed said.

The raid comes as the military is set to launch an assault against Mehsud’s group in the South Waziristan region, on the Afghan border.

“We raided the house on a tip-off that militants were planning attacks in the city,” Ahmed told the Reuters news agency.

“As we reached near the house, they opened fire. Our force returned the fire and five militants were killed.”

Al Jazeera’s Imran Khan, reporting from Karachi, said the gun battle took place in a dangerous neighbourhood of Karachi.”Many people fear going into that neighbourhood unless they can speak the local language which is Pashtun in that particular neighbourhood.

“It is a very difficult area for anybody who is not a member of that community to go into.”

“The raids are adding to the ethnic tension that is already very high in Karachi.”

‘Taliban infiltration’

Fears have been growing over the past few months that Taliban fighters fleeing an army offensive in the country’s the northwest are infiltrating into Karachi, the country’s commercial capital.

The Pakistani military has in recent days expanded an operation against fighters in the North West Frontier Province to neighbouring South Waziristan, targeting bases reportedly used by Mehsud.

The military has been launching air raids on Mehsud’s bases this month while soldiers have been securing main roads and sealing off his stronghold.

Mehsud is a close al-Qaeda ally and his followers have responded with a campaign of attacks, including suicide blasts, across the country.

On Friday, two soldiers were killed and several others wounded after a suicide bomber attacked an army vehicle in Pakistan-administered Kashmir.

It was the first suicide attack in the Pakistani part of Kashmir, according to Choudhry Imtiaz, a senior administrative official. – Al Jazeera