At least 37 people have been killed and 90 injured in a suicide bombing following an election rally in northwestern Pakistan.  The bombing comes as politicians in Pakistan were wrapping up their campaigns for Monday's parliamentary elections.  VOA correspondent Meredith Buel has details from Islamabad.

Security officials say the blast occurred when a suicide bomber rammed his car into a group of people leaving a rally for a local candidate supported by the party of the slain leader, Benazir Bhutto.

The attack came in the town of Parachinar, in the troubled Kurram tribal region bordering Afghanistan.

Many of the injured are in critical condition and the death toll is expected to rise.

The campaign for Monday's parliamentary elections has been overshadowed by security fears following the assassination of former Prime Minister Bhutto in a gun and suicide bomb attack last December.

Most of the victims in this latest blast appear to be supporters of Ms. Bhutto's Pakistan People's Party.

A wave of suicide bombings has caused bloodshed across Pakistan in recent weeks.

Pakistan's interior minister, Hamid Nawaz Khan, is the top government official responsible for security for the elections.

Khan tells VOA that incidents like the latest bombing are sowing fear among voters and could have a negative impact on turnout at the polls.

"This incident, one more incident like this, where lives get lost and a large number of people get injured, it definitely does affect the people," he said.  "It does create an environment of fear, but at the same time we have to surmount this difficulty."

Pakistan has deployed more than 80,000 soldiers and hundreds of thousands of police and paramilitary forces throughout the country in an effort to provide security for the election.

Interior Minister Khan says with more than 64,000 polling stations it is difficult to protect all of them from suicide bombers.

"So this type of ugly incident, there is a possibility that it could occur on one or two places," he added.  "But in a country which is so big, a population of about 160 million people, the degree of risk I would say is insignificant when you see it in terms of percentages or the possibilities."

Monday's elections will take place against a backdrop of rising Islamic militancy throughout Pakistan and many candidates have been discouraged from holding large rallies.

Security fears are running highest in the lawless tribal areas along the Afghan border.

The elections are considered crucial to restoring democracy to Pakistan following eight years of military rule under President Pervez Musharraf.

Mr. Musharraf's presidency is not being contested in this election, but if opposition parties win a two-thirds majority in parliament, they would have enough votes to impeach him.