KABUL (Reuters) - The number of people killed when a bomb went off at an election rally in northeastern Afghanistan has climbed to at least 22, officials said on Saturday.

The explosion happened in Takhar province where scores of people had gathered to listen to a speech by a woman standing as a candidate in the parliamentary polls on Oct. 20.

Jawad Hejri, spokesman for Takhar governor, said at least 22 people died and 36 were wounded in the attack, in Rustaq district.

Explosives had been placed on a motorcycle near the rally, which was to have been addressed by the candidate, Nazifa Yousufi Bek.

The victims included security officials and civilians, a local police official said, adding that the candidate was not at the rally at the time.

No militant group immediately claimed responsibility for the attack. It is the third attack against the election campaign process this month.

Bek is one of 417 women contesting seats across the country, more than ever before.

Candidates, regardless of gender, are braving violence and opposition from social conservatives in a campaign seen as a test of the war-torn nation’s democratic institutions.

Seven candidates, all men, have been killed in separate attacks so far. Another two have been abducted, and four others have been wounded by hardline Islamist militants, election officials said.

Takhar, a province bordering Tajikistan, has long been a hotbed of the Taliban insurgency. The Taliban have told Afghans to boycott the upcoming polls.

In the western province of Herat, gunmen attacked the election campaign office of a candidate, killing a security guard and a child, said Jailani Farhad, a spokesman for the Herat governor.

President Ashraf Ghani condemned the attacks in a statement, saying that the enemies of Afghans cannot weaken the will of the nation.

US ambassador to Afghanistan John Bass condemned the violence, and called on the Taliban to do the same.

“If the group (the Taliban) is serious about the peace process it will do the same and punish those responsible,” he said in a tweet.