Two dead, 25 injured in explosion at Afghan vice presidential candidate's office

July 28 (UPI) -- Two people died and dozens more, including Afghan vice presidential candidate Amrullah Saleh, were injured in an explosion in Kabul on Sunday.

Afghanistan's Health Ministry said one of the people killed in the explosion was a woman and Afghan Interior Ministry spokesman Nasrat Rahimi said at least 25 people were injured in the blast near Saleh's Kabul office.

Saleh, President Ashraf Ghani's running mate for the upcoming Sept. 28 presidential election, was injured by shrapnel from the bomb but was safely evacuated.

Rahimi said attackers detonated a car bomb near the office and four gunmen stormed the office and engaged in a standoff with Afghan security forces.

He added that at least one of the attackers had been killed and two others were still battling Afghan forces.

There was no immediate claim of responsibility for the attack, which took place on the first day of campaigning for the election.

Zalmay Khalilzad, the U.S. special representative for Afghanistan Reconciliation, condemned the attack in "the strongest terms."

"That attack on Amrullah Saleh's political party offices was grotesque and a clear act of terrorism," he said on Twitter, adding "the perpetrators should be brought to justice. We stand with Afghanistan in the fight against terror."