Four people are dead and at least 35 others are wounded after at least one bomb exploded Thursday in Karachi, two days before President Bush's arrival in Pakistan.
Local officials suspect a suicide car bomber set off the blast, which triggered a second explosion in the gas tank of a nearby vehicle.
The blasts occured about 20 meters from the United States consulate in a parking area outside an American-operated hotel. The explosions started fires in several cars.
Mr. Bush, who has been holding talks in India today, is scheduled to arrive in Islamabad on Saturday. The Pakistani capital is more than 1,500 kilometers from Karachi, which is known as a hotbed of militant activity.
The U.S. consulate in Karachi has been a target for a number of attacks by militants in recent years, including a major bomb blast in 2002 that killed 14 people.
Mr. Bush will be meeting in Islamabad with President Pervez Musharraf, who plans to ask the U.S. leader to support Islamic leaders seeking safeguards against any future insults to their religious beliefs similar to the recent controversy surrounding cartoons of the Prophet Muhammad.
Opposition groups in Pakistan is planning another round of nationwide rallies on Friday to condemn the cartoons (published in some European newspapers) depicting Muhammad as a terrorist.
Some information for this report was provided by AFP, AP and Reuters.