Originally posted by the Voice of America. Voice of America content is produced by the Voice of America, a United States federal government-sponsored entity, and is in the public domain. Bomb Again Targets Pakistani Navy Bus VOA News April 28, 2011 Security officials collect evidence at the site of a bomb blast in Karachi, April 28, 2011 Photo: Reuters Security officials collect evidence at the site of a bomb blast in Karachi, April 28, 2011 Pakistani officials say a roadside bomb has hit a bus carrying navy personnel in Karachi, killing five people and wounding at least five others. A navy spokesman said the blast Thursday killed four navy employees and a civilian on a motorcycle. It was the third such attack this week in the southern port city, which is the main base for Pakistan's navy. The Taliban has claimed responsibility for Thursday's blast, as well as for a pair of bombings Tuesday that also targeted buses carrying navy personnel. Those attacks killed four people and wounded more than 50 others. The Taliban has vowed more strikes against security forces. Karachi is Pakistan's economic hub and its largest city with roughly 16 million people. It has been plagued by criminal, sectarian and militant violence. The attacks come days after Pakistan's army chief said his forces have "broken the back" of insurgents linked to the Taliban and al-Qaida. Army General Ashfaq Kayani said Saturday that Pakistan is fully aware of the internal and external threats to the country. Pakistan has launched several offensives against militants in the northwest along the Afghan border, but bombings and suicide attacks have continued. Earlier this month, the United States criticized Pakistan's counterterror efforts, saying the country had no clear path to defeating Taliban and al-Qaida-linked militants in the border region. The top U.S. military commander, Admiral Mike Mullen, also said some members of Pakistan's military intelligence agency have a long-standing relationship with Haqqani militants fighting in Afghanistan. Pakistan has denied any link with the al-Qaida affiliated group, and Kayani has rejected criticism of the country's efforts in the war on terrorism. Some information for this report was provided by AP, AFP and Reuters. .