An explosion followed by bursts of gunfire have been heard near Kabul International Airport in the Afghan capital.
Smoke was also seen rising above the facility, which is used by civilians and the military, a Reuters witness said.
NBC News Chief Foreign Correspondent Richard Engel, who is in the Afghan capital Kabul, wrote on Twitter:
The Taliban have claimed responsibility for a rocket attack on the Independent Election Commission (IEC) in the Afghan capital Kabul.
This is the second attack launched against an IEC office this week, as the Islamist insurgency seeks to derail the April 5 election it claims is a "Western-backed sham".
Armed men have attacked the Afghan election commission with rockets and gunfire one week before the presidential elections begin.
One warehouse in the compound is currently on fire after it was hit by a rocket-propelled grenade, Associated Press reported.
Police Chief General Mohammad Zahir said the group entered a building 800 metres (2,624 feet) from the Independent Election Commission, adding, "The fighting is still ongoing."
Heavy security has been sent to the Independent Election Commission headquarters in Kabul as gunfire and blasts were reported around the building compound.
NBC News Chief Foreign Correspondent Richard Engel reported from the Afghan capital Kabul:
An explosion followed by gunfire targeted a building close to the Independent Election Commission headquarters in Kabul, Reuters reported, citing staff and police.
"We can only confirm that a number of armed insurgents have entered a building close to the Independent Election Commission," Kabul's police chief spokesman Hashmat Stanekzai said.
Four people have been trapped in a guesthouse under attack by Taliban insurgents in the Afghan capital Kabul, the US-based aid group Roots for Peace said.
"I can confirm it was attacked and that there are only four people [inside]," country manager Hajji Mohammad Sharif Osmani told Reuters. "The rest of the guys are outside."
A witness told the news agency they saw more than 10 people who appeared to be foreign nationals being evacuated from the building.
Osmani said that most of the group's staff had been rescued and no one was known to have been killed.
Two children were among the victims of the Serena Hotel attack in Kabul, officials have said.
Four Taliban fighters snuck into the hotel early on Thursday evening and hid for three hours before storming into the restaurant and opening fire on people inside, according to interior ministry spokesman Sediq Sediqqi.
They then battled Afghan special forces for more than an hour inside the hotel before being overwhelmed, as terrified guests hid in rooms or fled to bunkers inside.
The foreign nationals killed were from Canada, India, New Zealand and Pakistan, the interior ministry said. The victims included four women, three men and two children.
Guns and ammunition used by attackers at the Serena hotel in Kabul have been shown to the media by Afghan intelligence officers.
Four gunmen were killed by special forces after they unleashed an attack on the luxury hotel in Kabul, killing nine people in the hotel's restaurant.
The Taliban has said it was behind the attack at the hotel, which is popular with foreigners.