Four Pakistani navy personnel were killed Thursday when attackers bombed a bus taking them to work

Four Pakistani navy personnel were killed Thursday when attackers bombed a bus taking them to work, the third such assault in days in the country's biggest city of Karachi.
  
More than a dozen people were wounded in the attack in Faisal Avenue, one of the main roads in Pakistan's politically tense economic capital and port city, which NATO uses to ship supplies to troops in Afghanistan. A passing motorcyclist was also killed in the blast.
 
Two other navy buses were attacked on Tuesday, dealing a blow to the military just days after Pakistan's army chief General Ashfaq Kayani claimed his forces had "broken the back" of Taliban and Al-Qaeda-linked militants. "Now a total of four of our employees -- all sailors -- have been martyred in the attack on our bus while seven others are injured," spokesman Commander Salman Ali told AFP. Four other navy personnel died on Tuesday.
  
On the border Wednesday, Pakistan said one of its soldiers was killed and three wounded by "unprovoked firing" from Afghan troops, and that shops were also damaged and civilian casualties caused at a market in South Waziristan. A spokesman for the Afghan defence ministry, however, denied receiving any reports of border shooting.