KARACHI, Pakistan, Oct 7, (AP): A Pakistani separatist group claimed responsibility for a late night bombing that targeted a convoy with Chinese nationals outside the country's largest airport, killing two workers from China and wounding eight people, officials and the insurgent group said Monday. The attack by the Baloch Liberation Army outside the airport in the southern port city of Karachi was the latest deadly assault on Chinese here and came a week before Pakistan is to host a summit of the Shanghai Cooperation Organization, a security grouping founded by China and Russia to counter Western alliances.

The explosion, which the BLA said was the work of a suicide bomber, also raised questions about the ability of Pakistani forces to secure high-profile events or foreigners in the country. Among the wounded were also police officers who were escorting the Chinese convoy when the attack happened. Initially, Pakistani authorities gave conflicting details and said the explosion may have been from an oil tanker but police later confirmed it was a bomb attack. Pakistani news channels broadcast videos of flames engulfing cars and a thick column of smoke rising from the scene.

Troops and police cordoned off the area. On Monday, counterterrorism officials were investigating how the attacker reached Karachi, Pakistan's largest city. The spokesman for the separatist group, Junaid Baloch, said Monday that one of their suicide bombers targeted the convoy of Chinese engineers and investors as they left the airport. The Baloch Liberation Army is mainly based in the restive southwestern Balochistan province but it has also attacked foreigners and security forces in other parts of Pakistan in recent years.

The Chinese Embassy in Islamabad said Chinese staffers working at the Port Qasim Electric Power Company - a coal-powered power plant that's a joint China-Pakistan venture - were in the convoy when it came under attack around 11 p.m. on Sunday. Two Chinese nationals were killed and one was wounded, the embassy said and added, without elaborating, that there were also Pakistani casualties.