Kabul, Afghanistan (CNN) -- Nine people were killed Friday in a deadly roadside blast in Afghanistan that officials linked to the upcoming parliamentary vote.
The nine victims were traveling on a horse-drawn cart and included women and children, said Sherjan Durrani, spokesperson for the chief of police in Balkh province.
"The enemy knows there will be a lot of patrols by the police and the army, so they planted the explosives," Durrani said.
In other election-related violence, the Taliban kidnapped 18 people working on Saturday's voting in northwestern Afghanistan, a local government spokesman said Friday. And a political candidate was kidnapped in eastern Afghanistan, said Munir Mohmmad Mangal of the Interior Ministry.
However, a Laghman province spokesman said the candidate, Hayatullah Forqani, was in hiding to prevent being caught for campaigning after the deadline to do so had passed.
In Kabul, President Hamid Kazai acknowledged that the elections will face "difficulties" and "irregularities," but he encouraged Afghans to vote nonetheless.
"The elections ... are going to be facing difficulties and especially in Afghanistan under circumstances we must expect that there'll be irregularities, there'll be problems and there'll be allegations, as well, but we should try to do our best under the circumstances and make the elections a success," he said.
The 10 campaign workers and eight Afghan Independent Election Commission employees were kidnapped Thursday night in the village of Kolagai, said a spokesman for Sharafudin Majid, the Badghis province governor.
The workers were campaigning for candidate Zia Alekozai in a remote area in Badghis province.
On Wednesday, Taliban fighters killed two workers from Afghanistan's main election body.
That attack occurred in a remote district of Afghanistan's northern Balkh province.
The Taliban has threatened to target polling stations during the voting. Security remains a key concern for Afghanistan's Independent Election Commission.
The commission said Friday that 89 percent of the nearly 19,000 polling stations were ready to open at 7 a.m. Saturday. It acknowledged that security issues could keep some polls closed.
Afghanistan's Interior Ministry announced it will deploy 52,000 police, soldiers and national security officers on election day. They will be complemented by troops from Afghanistan's NATO-led International Security Assistance Force.
Meanwhile, the U.S. Embassy in Kabul has issued a new warning of potential violence surrounding the elections. It alerted U.S. citizens to avoid crowds and public gatherings and said some road closures and checkpoints at polling stations are to be expected.
And the United Nations encouraged international employees not involved with supporting the election to take leave during the polling.