Two bomb blasts have rocked Pakistan's second-largest city, killing at least 26 people and injuring 200 others. One of the explosions occurred at the headquarters of a federal police agency, packed with workers. VOA correspondent Steve Herman reports from Islamabad.

Shortly after the workday began at the multi-story Lahore headquarters of the Federal Investigation Agency, a powerful explosion tore through the building, killing many employees. Residents living kilometers away say the blast was so strong that it rattled windows and shook walls in their homes.

The city's police chief, Malik Mohammed Iqbal, told reporters on the scene there is no doubt it was a terrorist attack.

"It's a suicide bomb blast in the sense that a vehicle full of explosives forced its way into FIA  headquarters," he said. "It exploded near the main building."

Dazed survivors, some with their clothing torn, could be seen standing amid the rubble watching rescuers remove the bodies of their colleagues.

A separate blast, around the same time 15 kilometers away in a high-security, upscale residential area, killed at least four people, including two children. That explosion destroyed a house rented to a medium-sized advertising agency, which has multi-national corporations as clients. The chief executive officer of the SB&B agency told reporters he has no idea why his company would have been targeted and it might have been a situation of mistaken identity.

Local media report the adjacent house is owned by a retired judge, whose son is a police officer. Witnesses say a van drove into the driveway of the bungalow and the vehicle exploded, flattening the house.

The provincial government of Punjab blames both attacks on suicide bombers using explosive-laden vehicles.

The Tuesday morning blasts came a week after two suicide bombings at a naval college in Lahore. Those attacks killed at least five people.

Police chief Iqbal says the latest attacks will not shake the resolve of his forces to combat suicide bombers.

"This does not mean that we will surrender, we will make more stringent security measures so that such type of incidents do not take place," he said.

There have been six bombings since the February 18 national elections. The two largest opposition parties are attempting to form a new government that will face public pressure to remove President and former General Pervez Musharraf, a strong ally of the United States in its anti-terrorism campaign.

Hours after the Lahore blasts, Mr. Musharraf called for the new National Assembly to convene in Islamabad next Monday.

The president strongly condemns the latest bombings, calling them a "savage act" that would not deter the government's resolve to fight the scourge of terrorism with full force.

Shortly after Tuesday's explosions, Pakistan's cricket board announced the Australian national team was canceling a planned upcoming tour of the country because of security concerns.