KABUL, Sept. 17 (Xinhua) -- Casualties were feared after an explosion struck an election campaign rally in Afghanistan's eastern Parwan province on Tuesday, local police said.

"The incident occurred roughly at midday when a sticky bomb attached into a motorcycle was detonated outside a compound where the meeting was held," Mohammad Salim Noori from provincial police told Xinhua.

He said further details about the incident will be available later in the day.

"The gathering was held by campaign office of incumbent President Ashraf Ghani. So far, we have no more details, but we will try to get more information," a security source said.

"President Ghani and his running mate Amrullah Saleh were safe after the explosion occurred outside the compound where they held campaign rally in provincial capital Charikar city," he said.

Security forces have cordoned off the area for precautionary measures.

No group has claimed responsibility for the attack yet.

The Taliban insurgent group fighting the government has vowed to disrupt the election process.