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KABUL, March 25 (Reuters) - An explosion and gunfire rattled the house of Afghan presidential candidate Ashraf Ghani on Tuesday, a senior police officer said, although Ghani was not there at the time.
The Afghan capital is on high alert ahead of an April 5 presidential election which Taliban insurgents have threatened to disrupt through a campaign of bombings and assassination.
"Four people entered Ashraf Ghani's house and there was an explosion followed by gunfire," the officer told Reuters.
A Reuters cameraman near Ghani's house said he could hear continuous gunfire.
Ghani, in a Tweet sent after the attack, said: "Just arrived at Gardez rally, a huge crowd of tens of thousands." Gardez is in a volatile area south of Kabul.
There were no immediate reports of casualties. Ghani is a former World Bank official who has picked powerful former Uzbek warlord Abdul Rashid Dostum as his running mate.
(Reporting by Hamid Shalizi; Writing by Maria Golovnina; Editing by Paul Tait)