Media playback is unsupported on your device Media caption The BBC's Harun Najafizada visited the scene of the attack

The Taliban have launched a gun and bomb attack on an office of the Afghan election commission in Kabul, less than two weeks before presidential polls.

Two policemen were killed and two others wounded in the battle with the insurgents, the interior ministry said, adding that five gunmen were also dead.

There were no immediate reports of casualties among election workers.

The Taliban, who have vowed to disrupt the 5 April vote and are boycotting it, said they carried out the attack.

Reports said fighting was still going on, four hours after it began.

"At around 11:35 am [07:05 GMT] a suicide bomber blew himself up at the gate of an IEC [Independent Election Commission] regional office in Darulaman, and then several other attackers entered the building," a Kabul police spokesman is quoted as saying by the AFP news agency.

"Cleaning up" operations were going on at the election commission compound on the city's outskirts, an interior ministry spokesman said.

Initial reports said the nearby home of candidate Ashraf Ghani had come under fire, but shortly afterwards, police said the provincial election headquarters was the focus of the attack.

It was not immediately clear how many attackers were involved in the assault on the election commission compound.

The attack is the latest in the run-up to the vote to choose a successor to President Hamid Karzai.

Mr Ghani is a former finance minister and World Bank official, and a leading candidate in the race to succeed Mr Karzai. He is running for election on a ticket with the former Uzbek warlord Abdul Rashid Dostum.

In a separate incident on Tuesday, three suicide bombers stormed the government-owned Kabul Bank in the eastern province of Kunar.

Governor Shajawil Mulk Jalal told the BBC five people died in the attack, including one civilian and four Afghan security forces.