At least nine people, including two policemen, have been killed in a suicide attack at a funeral of a tribal elder in Afghanistan's Baghlan province, police officials have said.

Aminullah Amarkhil, the police chief of the northern province, said at least 20 others were wounded in Monday's attack in Burka District.

Taj Mohammad Taqwa, the district chief of Burka, confirmed the death toll to AFP news agency.

"The target was probably a number of high-ranking police officials and provincial council members who were attending the ceremony," he said. "They are unharmed."

There was no immediate claim of responsibility.

Monday's blast comes after a spate of attacks in Kabul, the Afghan capital, in recent weeks, as US-led NATO forces prepare to wrap up a 13-year combat mission against the Taliban.

Fighters have targeted foreign guest houses, embassy vehicles, US troops, Afghan army buses and a female member of parliament in recent weeks.

They also launched a four-day attack on a major military base in the southern province of Helmand that was only handed over by NATO a month ago, and killed 12 soldiers at a separate outpost in the same province on Saturday.

Afghan soldiers and police have suffered soaring casualties on the battlefield, with more than 4,600 killed this year as they take on the Taliban with less assistance from the US military.

Afghanistan faces a fragile economy and declining aid funds as well as worsening violence.

Ghani and chief executive officer Abdullah Abdullah will visit NATO headquarters in Brussels Monday before attending a conference in London in a public show of unity after they signed a power-sharing deal in September.

NATO troop numbers in Afghanistan peaked at 130,000 in 2010, and fears are growing that the declining international presence will lead to an increase in Taliban activity.

Source: Al Jazeera and agencies