UPDATE, 9:30 a.m. ET: The attack appears to be over:

#Afghan security sources tell @ that all attackers have been shot dead and the siege on the Afghan election commission is over.
Militants Attack Afghan Election Office In Kabul
Richard Engel

KABUL, Afghanistan (AP) — Police say militants have occupied a building in Kabul and are shooting at the main Afghan election commission’s compound.

A police officer at the scene, Jan Agha, says the attackers have not entered the International Election Commission’s compound, which is heavily secured. He says the attackers are about 500 meters (yards) from the compound in a three-story house. He says there’s no immediate information about casualties.

It’s the latest in a series of high-profile attacks that come as the Taliban have stepped up a campaign of violence to disrupt presidential elections, which are due to be held in a week.