A Taliban suicide attacker has killed three people on an Afghan army bus in Kabul.

Scores of shuttle buses take government and military personnel to work every morning in the capital, and they have often been targeted by insurgents despite efforts by security forces to provide better protection.

It was the fourth high-profile attack in the capital since new president Ashraf Ghani was sworn in on Monday, and the Taliban has warned of further attacks.

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On Wednesday, Taliban suicide bombers killed at least seven people in twin attacks on two buses.

The militant group strongly opposes a US-Afghan troop agreement that was signed on Tuesday to allow the foreign soldiers to stay in the country.

“I can confirm a suicide attack on a bus carrying Afghan army staff,” said Dawlat Waziri, deputy spokesman for the ministry of defence.

“We have three killed and eight wounded.

“The wounded were immediately taken to the hospital, and they are in a stable condition.”

A police statement confirmed the death toll and injured.

Taliban spokesman Zabihullah Mujahid said in a text message: “Around 7am, a suicide attacker targeted a bus carrying Afghan security forces, as a result, a number of officers were killed and wounded.”

Afghanistan and the United States on Tuesday signed the long-delayed bilateral security agreement (BSA) to allow about 10,000 US troops to stay in the country next year.

The signing took place on newly-inaugurated President Ashraf Ghani’s first day in office and represented a major step towards mending frayed ties between Afghanistan and the US.