Suicide bombers have attacked the compound of a provincial governor in Afghanistan's northern Parwan province, killing at least 22 people.

Officials said 16 civilians and six police officers had been killed and at least 33 others injured in the attack on Sunday.

A standoff in the area lasted about 50 minutes, with the Taliban claiming responsibility for the attack in Charikar, the provincial capital.

"Our initial reports suggest at least six explosions," Sediq Seddiqi, spokesman for the Afghan Ministry of Interior, told Al Jazeera.

Seddiqi said gunmen, wearing explosive vests, approached governor Abdul Basir Salangi's compound. One of them detonated himself at the gate, while the others entered the compound.

"The attack began around noon, and there is a clearance operation underway," he said.

The governor spoke to local television from inside the compound, saying he was fine but his forces were battling the remaining fighters.

"One of the attackers made it to the front door of my office and I shot him down," Salangi told ToloNews.

Parwan lies about an hour's drive northwest of the capital Kabul.

Al Jazeera's Charles Stratford, reporting from Kabul, said the Taliban had claimed responsibility for the attack about 15 minutes after the incident.

"Parwan has been considered one of the safest provinces. This attack again highlights how vulnerable some of these provinces are that attackers can seemingly penetrate at will," he said.

The Bagram Airbase, which is the largest US base in Afghanistan, is also in Parwan.

High-profile targetings

The attack is the latest in a trend of high-profile targetings that the Taliban have claimed responsibility for.

In July, three major figures in southern Afghanistan, including Afghan president Hamid Karzai's influential half-brother Ahmad Wali, were assassinated.

"In May, the Taliban made a statement saying they were expanding their operations as part of their Operation Badr," said Stratford. "It seems like that is happening now."

Northern Afghanistan, including Parwan, was relatively peaceful during the first few years of the war against al-Qaeda and the Taliban.

In the past couple years, after security deteriorated in the area, the government launched an offensive to restore security.

General Daud Daud, the police chief of northern zone who led the operations, was assassinated in May, derailing the progress.